CI/CD rate limit improvements

[spencerschrock]

Currently we run every check on PRs when submitted, commits pushed to the PR source branch, etc.

If we break the actions into light/heavy we could save some API limits.

Light (think unit tests) get run on every commit, heavy (e2e) get run once the pull request is approved and ready to merge.

Maybe this trigger since we need an approval for lastest commits anyway?
https://docs.github.com/en/actions/using-workflows/events-that-trigger-workflows#running-a-workflow-when-a-pull-request-is-approved

Or something with labels(https://docs.github.com/en/actions/using-workflows/events-that-trigger-workflows#pull_request_target) if we want certain failures to be surfaced sooner.

[spencerschrock]

We will likely need to revert this.
https://docs.github.com/en/actions/using-workflows/events-that-trigger-workflows#workflows-in-forked-repositories-1

This is causing the integration tests to fail since they can't access secrets. Secrets are accessible through pull_request_target, so any filtering would need to be done with that trigger.

[github-actions]

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