Logger is not configured correctly

[ixdy]

Looking at logs from a recent boskos build (from this repo) reveals that some things are not configured appropriately:

boskos:

{"component":"unset","file":"/go/pkg/mod/github.com/sirupsen/logrus@v1.4.2/entry.go:314","func":"github.com/sirupsen/logrus.(*Entry).Logf","handler":"handleUpdate","level":"info","msg":"From 10.44.2.234:42282","time":"2020-06-05T23:01:09Z"}

cleaner:

{"component":"unset","file":"/go/pkg/mod/github.com/sirupsen/logrus@v1.4.2/logger.go:192","func":"github.com/sirupsen/logrus.(*Logger).Log","level":"info","msg":"Cleaner started","time":"2020-06-05T22:47:27Z"}

etc.

The component is unset because we aren't setting the variables in k8s.io/test-infra/prow/version.
We can fairly easily add linker flags for this, though it'll require a bit of work in the Makefile (or maybe we'll just want to write a wrapper script).

I'm not sure why we're getting useless file and function annotations, though.

/kind bug

[ixdy]

The caller information being incorrect is sirupsen/logrus#1096. We'll need to update our logrus dependency.