* ci: Convert all Go tests into a single job

Takes all the go-e2e and go-test jobs and combines them into one single super-job. This has the following benefits:

1. We can centralize all config for Go tests in one place and simplify our CI pipeline.
2. It leaves parallelism up to the Go runtime, which is more efficient.
4. It makes our test reporting more accurate.

As part of this PR, I also:

1. Created a new resource class just for Go tests. It runs on the large Latitude runner, but limits the number of parallel go test jobs to 3 to prevent resource starvation.
2. Enabled test retries on `gotestsum`. This should reduce the number of flakes we see from the Go tests by retrying them up to 2 times in the event that they fail. Failures are still captured by the test reporting, so we can address them.

* code review updates