This commit makes a few notable changes:
1. Use the GitHub Actions automatic token for committing changes
2. Include workflow file in paths to trigger workflow
3. Checkout the default branch explicitly
Fixes#11270
This commit refactors the work done in #11047 of blocking pull requests for manual `third-party` license updates to having GitHub Actions automatically update it on pushes to `trunk`.
This will allow maintainers to streamline Dependabot PR reviews while reducing contributor friction when changing dependencies.
