Fix GO_MODULES linter CI action

[bstoll]

We used to use super-linter v5 with go checks disabled (example). When updating to v8 this was reintroduced because of a new GO_MODULES check (example). We should look into these and see if we can get this check enabled again.

GO_MODULES
  2025-08-27 06:09:46 [INFO]   Linting GO_MODULES items...
  Error: -27 06:10:44 [ERROR]   Found errors when linting GO_MODULES. Exit code: 1.
  2025-08-27 06:10:44 [INFO]   Command output for GO_MODULES:
  ------
  ../../../github/workspace/dhcp/dhcp.go:143:23: Error return value of `instance.server.Wait` is not checked (errcheck)
  		instance.server.Wait()
  		                    ^
  ../../../github/workspace/server/entitymanager/entitymanager_test.go:199:6: Error return value is not checked (errcheck)
  	em, _ := New("", a)
  	    ^
  ../../../github/workspace/server/entitymanager/entitymanager_test.go:408:6: Error return value is not checked (errcheck)
  	em, _ := New("", nil)
  	    ^
  ../../../github/workspace/server/server.go:57:21: Error return value of `s.httpSrv.Shutdown` is not checked (errcheck)
  		s.httpSrv.Shutdown(context.Background())
  		                  ^
  ../../../github/workspace/client/client.go:197:1: cyclomatic complexity 22 of func `main` is high (> 15) (gocyclo)
  func main() {
  ^
  ../../../github/workspace/client/client.go:242:47: G402: TLS InsecureSkipVerify may be true. (gosec)
  	tlsConfig := &tls.Config{InsecureSkipVerify: !*verifyTLSCert}
  	                                             ^
  ../../../github/workspace/client/client.go:352:15: G402: TLS MinVersion too low. (gosec)
  	tlsConfig = &tls.Config{
  		InsecureSkipVerify: false,
  		RootCAs:            trustCertPool,
  	}
  ../../../github/workspace/dhcp/plugins/bootz/bootz.go:59:46: G115: integer overflow conversion int -> uint16 (gosec)
  		b = binary.BigEndian.AppendUint16(b, uint16(len(u)))
  		                                           ^
  ../../../github/workspace/server/server.go:115:10: G402: TLS MinVersion too low. (gosec)
  	tls := &tls.Config{
  		Certificates: []tls.Certificate{*sa.TLSKeypair},
  		RootCAs:      trustBundle,
  	}
  ../../../github/workspace/server/server.go:170:10: G112: Potential Slowloris Attack because ReadHeaderTimeout is not configured in the http.Server (gosec)
  	srv := &http.Server{Addr: opt.Address, Handler: fs}
  	        ^
  ../../../github/workspace/client/client.go:292:6: shadow: declaration of "err" shadows declaration at line 209 (govet)
  		if err := validateArtifacts(controlCardState.GetSerialNumber(), resp); err != nil {
  		   ^
  ../../../github/workspace/client/client.go:298:5: shadow: declaration of "err" shadows declaration at line 209 (govet)
  	if err := proto.Unmarshal(resp.GetSerializedBootstrapData(), &signedResp); err != nil {
  	   ^
  ../../../github/workspace/client/client.go:317:10: shadow: declaration of "err" shadows declaration at line 209 (govet)
  		image, err := downloadImage(data.GetIntendedImage().GetUrl())
  		       ^
  ../../../github/workspace/server/entitymanager/entitymanager.go:152:5: shadow: declaration of "err" shadows declaration at line 147 (govet)
  	if err := prototext.Unmarshal(data, gnsiAuthzReq); err != nil {
  	   ^
  ../../../github/workspace/server/service/service.go:205:13: shadow: declaration of "err" shadows declaration at line 166 (govet)
  		bootdata, err := s.em.GetBootstrapData(ctx, chassis, v.GetSerialNumber())
  		          ^
  ../../../github/workspace/server/service/service.go:213:13: shadow: declaration of "err" shadows declaration at line 166 (govet)
  		bootdata, err := s.em.GetBootstrapData(ctx, chassis, chassisDesc.GetSerialNumber())
  		          ^
  ../../../github/workspace/server/server.go:120:2: ineffectual assignment to s (ineffassign)
  	s := &grpc.Server{}
  	^
  ../../../github/workspace/dhcp/dhcp.go:93:24: var-declaration: should drop = nil from declaration of var instance; it is the zero value (revive)
  var instance *Server = nil
                         ^
  ../../../github/workspace/dhcp/plugins/bootz/bootz.go:39:2: var-naming: don't use ALL_CAPS in Go names; use CamelCase (revive)
  	OPTION_V4_SZTP_REDIRECT uint8 = 143
  	^
  ../../../github/workspace/dhcp/plugins/bootz/bootz.go:40:2: var-naming: don't use ALL_CAPS in Go names; use CamelCase (revive)
  	OPTION_V6_SZTP_REDIRECT uint8 = 136
  	^
  ../../../github/workspace/server/entitymanager/entitymanager.go:60:48: unused-parameter: parameter 'ctx' seems to be unused, consider removing or renaming it as _ (revive)
  func (m *InMemoryEntityManager) ResolveChassis(ctx context.Context, lookup *service.EntityLookup, ccSerial string) (*service.Chassis, error) {
                                                 ^
  ../../../github/workspace/server/entitymanager/entitymanager.go:188:50: unused-parameter: parameter 'ctx' seems to be unused, consider removing or renaming it as _ (revive)
  func (m *InMemoryEntityManager) GetBootstrapData(ctx context.Context, chassis *service.Chassis, serial string) (*bpb.BootstrapDataResponse, error) {
                                                   ^
  ../../../github/workspace/server/entitymanager/entitymanager.go:324:74: redefines-builtin-id: redefinition of the built-in function new (revive)
  func (m *InMemoryEntityManager) ReplaceDevice(old *service.EntityLookup, new *epb.Chassis) error {
                                                                           ^
  ../../../github/workspace/server/service/service.go:301:42: unused-parameter: parameter 'ctx' seems to be unused, consider removing or renaming it as _ (revive)
  func (s *Service) SetDeviceConfiguration(ctx context.Context) error {
                                           ^
  ../../../github/workspace/client/client.go:181:36: SA1019: cc.GetSlot is deprecated: Marked as deprecated in github.com/openconfig/bootz/proto/bootz.proto. (staticcheck)
  			slotPopulated := populatedSlots[cc.GetSlot()]
  			                                ^
  ../../../github/workspace/client/client.go:183:94: SA1019: cc.GetSlot is deprecated: Marked as deprecated in github.com/openconfig/bootz/proto/bootz.proto. (staticcheck)
  				log.Exitf("Chassis validation error: slot %d already populated by another control card", cc.GetSlot())
  				                                                                                         ^
  ../../../github/workspace/client/client.go:185:19: SA1019: cc.GetSlot is deprecated: Marked as deprecated in github.com/openconfig/bootz/proto/bootz.proto. (staticcheck)
  			populatedSlots[cc.GetSlot()] = true
  			               ^
  ../../../github/workspace/server/entitymanager/entitymanager.go:175:37: unnecessary conversion (unconvert)
  		cliConf, err := os.ReadFile(string(conf.VendorConfigFile))
  		                                  ^
  ../../../github/workspace/server/emulator/main.go:36:2: var dhcpIntf is unused (unused)
  	dhcpIntf        = flag.String("dhcp_intf", "", "Network interface to use for dhcp server.")
  	^
  29 issues:
  * errcheck: 4
  * gocyclo: 1
  * gosec: 5
  * govet: 6
  * ineffassign: 1
  * revive: 7
  * staticcheck: 3
  * unconvert: 1
  * unused: 1
  0 issues.
  Linted: /github/workspace/proto/bootz
  0 issues.
  Linted: /github/workspace/server/entitymanager/proto/entity