chore: onboard compute to owlbot

[codyoss]

No description provided.

[noahdietz]

There is a nasty hack to add an extra generator flag specifically for compute:

google-cloud-go/internal/gapicgen/generator/gapics.go

Lines 323 to 326 in 7a9e211

	// This is a bummer way of toggling diregapic generation, but it compute is the only one for the near term.
	if conf.Pkg == "compute" {
	args = append(args, "--go_gapic_opt", "diregapic")
	}

There is a bazel equivalent I believe. I just remembered this, sorry face palm

[noahdietz]

LGTM once googleapis/googleapis#793 is in