Adding PAKETO_BOT_GITHUB_TOKEN on checkout as github_token

[pacostas]

Summary

This PR adds PAKETO_BOT_GITHUB_TOKEN on checkout as the github_token. This allows to trigger the test workflows and also trigger the auto approve action. Currently, only the first commit triggers the aforementioned actions as the PR is happening from the open pr gh actions, which uses the PAKETO_BOT_GITHUB_TOKEN. In case something blocks the PR and can not be landed (e.g. GH sometimes is flaky) the subsequent commits are getting pushed with the GITHUB_TOKEN instead of the PAKETO_BOT_GITHUB_TOKEN . This results in not triggering the aforementioned the github actions and it ends up the automated updates, needing a manual approval/review, which might be missed.

This PR will unblock many stale PRs :) and will also improve the maintenance on the Paketo Buildpacks overall !

Use Cases

Checklist

• I have viewed, signed, and submitted the Contributor License Agreement.
• I have linked issue(s) that this PR should close using keywords or the Github UI (See docs)
• I have added an integration test, if necessary.
• I have reviewed the styleguide for guidance on my code quality.
• I'm happy with the commit history on this PR (I have rebased/squashed as needed).