ci : Regarding the failure of the Go CI in GitHub Actions

[seipan]

It seems that the CI for Go is failing.

go test ./... -short -race
?   	github.com/vmihailenco/msgpack/v5/msgpcode	[no test files]
make: *** [Makefile:3: test] Terminated
Error: Process completed with exit code 143.

This seems to be an issue related to the usage of resources such as memory and CPU.
ref : actions/runner-images#6680

I think the current situation with the CI failing is not very good, so I believe we should remove 'go test -race'.