PRO-760: Changed required-checks.yml to work on any branch

[252afh]

Context

Now that github has stacked PRs, we need all the checks to work on the entire stack, rather than just the final PR that targets main

Changes proposed in this pull request

• Remove the target branch from required-checks.yml so any branch triggers it

[linear-code]

PRO-760

[github-actions]

Claude finished @252afh's task in 15s —— View job

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PR Review

• Read changed files
• Provide review feedback

Removes the branches: [main] filter from required-checks.yml so CI runs on PRs targeting any branch — enabling stacked PR workflows.

Looks good. ✅