Add GHA to check invalid commits

[fyliu]

Overview

We need to create a GitHub Action to check invalid commits, and advise merging those PRs by squashing.

In order to keep the main branch tidy, we don't want to rebase PRs that contain fixup commits that fix issues within the PR. So we want to add a PR comment asking the merger to squash those PRs if they're unable combine the commits manually.

Action Items

• Create GHA to check commit titles in a PR for invalid messages
  • If found, generate a new comment in the PR advising the merger to either resolve the invalid commits or squash the commits when merging.
  • Do not fail the check. We want the PR to be merge-able.

Resources/Instructions

• commit message that shouldn't end up in main - [pre-commit.ci] auto fixes from pre-commit.com hooks