Add unit tests for cmd/activator/main.go.

[akyyy]

/area autoscale
/area monitoring
/area test-and-release

/kind dev

Expected Behavior

The activator should have unit tests for StatsReporter after #1689 is checked in.

Actual Behavior

We don't have much unit tests.

[markusthoemmes]

@akyyy any tests that come to your mind specifically for the stats reporter in the activator?

[akyyy]

This is about cmd/activator/main.go doesn't have unit tests.

[markusthoemmes]

I'm not sure there is something actionable in here. I glanced over the main.go file and didn't find anything super useful to test in there. @akyyy do you feel strongly about this? If so, could you provide some guidance on what you'd like to see tested here?

[akyyy]

I opened this issue based on a comment from old pr a while ago. It's outdated and I'm closing it. Thanks!