fix: add missing strict deps (#1629)

After trying to build some targets in googleapis I saw some build
errors for missing strict deps, so I added them.

Author: codyoss

rules_go_gapic/go_gapic.bzl

@@ -157,6 +157,7 @@ def go_gapic_library(
     "@com_github_google_uuid//:go_default_library",
     "@com_github_googleapis_gax_go_v2//:go_default_library",
     "@com_github_googleapis_gax_go_v2//apierror:go_default_library",
+    "@com_github_googleapis_gax_go_v2//iterator:go_default_library",
     "@com_github_googleapis_gax_go_v2//internallog:go_default_library",
     "@com_github_googleapis_gax_go_v2//internallog/grpclog:go_default_library",
     "@com_google_googleapis//google/rpc:status_go_proto",
@@ -174,6 +175,7 @@ def go_gapic_library(
     "@org_golang_google_grpc//status:go_default_library",
     "@org_golang_google_protobuf//proto:go_default_library",
     "@org_golang_google_protobuf//encoding/protojson:go_default_library",
+    "@org_golang_google_protobuf//runtime/protoimpl:go_default_library",
     "@org_golang_google_protobuf//types/known/emptypb:go_default_library",
     "@org_golang_google_protobuf//types/known/wrapperspb:go_default_library",
     "@org_golang_google_protobuf//types/known/fieldmaskpb:go_default_library",