Ensure `update-dependent-repositories` Workflow Runs for Dependabot Alert Merges

[bszirtes]

Description

Currently, Dependabot runs weekly to check for outdated GitHub Actions. If an update is found, it creates a pull request and merges it automatically. However, the update-dependent-repositories workflow is skipped in this process.

For repositories with Dependabot alerts enabled:

• Automated merging does not occur.
• When manually merging a PR created from a Dependabot alert, the update-dependent-repositories workflow is still skipped.

This behavior may be incorrect, as the workflow should run when merging security-related updates from Dependabot alerts.

Expected behavior

• Pull requests related to GitHub Actions updates (created by Dependabot) should be merged automatically, and the update-dependent-repositories workflow should be skipped for those.
• Pull requests created by Dependabot alerts should not be merged automatically.
• However, when a Dependabot alert PR is merged manually, the update-dependent-repositories workflow should be triggered.

Possible Fix

A prefix could be introduced for pull requests related to GitHub Actions (e.g., (github-actions)), which can be used to determine whether the update-dependent-repositories workflow should be executed later.