[Bug] Deprecated Node.js 12 actions are used

[oliverklee]

Describe the bug Then "On start" GitHub Action workflow is still using Node.js 12 (which is deprecated).

To Reproduce Steps to reproduce the behavior:

1. Create a new repository from this template.
2. Click on the Actions tab.
3. Click on the "On start" action
4. See error

Error message

Node.js 12 actions are deprecated. For more information see: https://github.blog/changelog/2022-09-22-github-actions-all-actions-will-begin-running-on-node16-instead-of-node12/. Please update the following actions to use Node.js 16: actions/checkout@v2

[sinsukehlab]

Already resolved in #23