Issues following Rekor Installation document

[andrew-m-leonard]

I have been following the Rekor Installation documentation, and come across the following issues:
doc: https://docs.sigstore.dev/logging/cli/

• go get -u -t -v syntax is now deprecated in favour of go install ...
• $GOPATH is not typically set by a standard Go installation
• Having installed the go modules under $HOME/go/pkg/mod/.... I found "go build" would always fail with:

github.com/google/trillian/cmd/trillian_log_server: go build github.com/google/trillian/cmd/trillian_log_server: copying /tmp/go-build327594267/b001/exe/a.out: open trillian_log_server: permission denied

I resorted to "git clone ..." which was far more reliable