relnotes: Sleep when hitting the secondary GH limit

[puerco]

What type of PR is this?

/kind bug
/kind failing-test
/kind flake

What this PR does / why we need it:

The last couple of releases have been hitting a new secondary rate limit
in the GitHub API. This PR makes some changes to play a bit more fair with
the API.

Now, the notes gatherer interprets the GitHub API response. If the
secondary rate limit was hit, the functions that make a lot of calls
will now sleep for a minute+random before respawning.

Signed-off-by: Adolfo García Veytia (Puerco) [email protected]

Which issue(s) this PR fixes:

Fixes #2225
Fixes #2302

/priority critical-urgent
/assign @justaugustus @Verolop @palnabarun @saschagrunert
/cc @kubernetes/release-engineering
/milestone v1.23

Special notes for your reviewer:

Note: this functionality should go into the github package in release-sdk (looking into this)

Does this PR introduce a user-facing change?

The release notes gatherer will now sleep for a minute+random secs when hitting the GitHub API secondary rate limit. 

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: puerco

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• pkg/notes/OWNERS [puerco]

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[puerco]

This PR adds the retry capability to the notes package. The permanent fix is here:
kubernetes-sigs/release-sdk#11

Merging this should enable us to cut the next beta and patches and we can revert it once release-sdk ships the fix in a release.

[Verolop]

/lgtm

[justaugustus]

Merging this should enable us to cut the next beta and patches and we can revert it once release-sdk ships the fix in a release.

@puerco -- This can be fixed more formally with the release of https://github.com/kubernetes-sigs/release-sdk/releases/tag/v0.4.0! 🎉

[puerco]

I'll revert to the fix in the package now that the new release is out (once we are done with patch releases)