ci: add a job that notifies dependencies when commits are made

[calebdoxsey]

Summary

When a commit is made to main or a release branch we should notify other repositories that an update was made.

Related issues

For ENG-4257

[coveralls]

Coverage Report for CI Build 29578876255

Warning

No base build found for commit a949754 on main.
Coverage changes can't be calculated without a base build.
If a base build is processing, this comment will update automatically when it completes.

Coverage: 100.0%

Details

• Patch coverage: No coverable lines changed in this PR.

Uncovered Changes

No uncovered changes found.

Coverage Regressions

Requires a base build to compare against. How to fix this →

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Coverage Stats

Relevant Lines:	7770
Covered Lines:	7770
Line Coverage:	100.0%
Coverage Strength:	20141.7 hits per line

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💛 - Coveralls

[kralicky]

Running this immediately might not work because it will take a little while for the updated binaries to be published. Is it possible to make this only trigger if all other workflows succeed?

Also sometimes we might not want to update right away on commits to main, like if there are incompatible api changes merged here which are then updated in a separate branch in pomerium. Not sure how to handle that exactly though. Maybe we can make the main-triggered workflow manual. But for release branches we do probably always want to update right away.