[8.15](backport #41583) x-pack/filebeat/input/entityanalytics/provider/okta: Rate limiting fixes

[mergify]

Proposed commit message

x-pack/filebeat/input/entityanalytics/provider/okta: Rate limiting fixes

- Separate rate limits by endpoint.
- Stop requests until reset when `x-rate-limit-remaining: 0`.

Checklist

• My code follows the style guidelines of this project
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have made corresponding change to the default configuration files
• I have added tests that prove my fix is effective or that my feature works
• I have added an entry in CHANGELOG.next.asciidoc or CHANGELOG-developer.next.asciidoc.

Discussion

Can be reviewed commit-by-commit.

The reason a new rate.Limiter needs to be created when x-rate-limit-remaining: 0 is that while rate.Limiter allows updating of the rate and burst, it doesn't allow clearing of existing tokens.

Disruptive User Impact

None.

Related issues

• Relates x-pack/filebeat/input/entityanalytics/provider/okta: Rate limiting hangs #40106

  ---

  This is an automatic backport of pull request x-pack/filebeat/input/entityanalytics/provider/okta: Rate limiting fixes #41583 done by Mergify.

[mergify]

Cherry-pick of 4e19d09 has failed:

On branch mergify/bp/8.15/pr-41583
Your branch is up to date with 'origin/8.15'.

You are currently cherry-picking commit 4e19d09ab2.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Changes to be committed:
	modified:   CHANGELOG.next.asciidoc
	new file:   x-pack/filebeat/input/entityanalytics/provider/okta/internal/okta/ratelimiter.go
	new file:   x-pack/filebeat/input/entityanalytics/provider/okta/internal/okta/ratelimiter_test.go
	modified:   x-pack/filebeat/input/entityanalytics/provider/okta/okta.go
	modified:   x-pack/filebeat/input/entityanalytics/provider/okta/okta_test.go

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   x-pack/filebeat/input/entityanalytics/provider/okta/internal/okta/okta.go
	both modified:   x-pack/filebeat/input/entityanalytics/provider/okta/internal/okta/okta_test.go

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally

[botelastic]

This pull request doesn't have a Team:<team> label.