Document the need for persist-credentials after actions/checkout.

[tim-schilling]

The git CLI commands expect the PAT to be stored in the git config.

Refs #610

Note, this doesn't address the monorepo docs. I wasn't 100% sure if it should also be updated since the configuration looked a bit older (checkout was using < v4). I'm happy to make edits as needed or to pass this off.

[github-actions]

End-to-end public repo

Admin commands cheatsheet:

• /e2e (in approved PR review body): Trigger end-to-end tests on external contributions
• /invite (in comment): Invite the author & admins to the end-to-end private repo

[github-actions]

Coverage report

This PR does not seem to contain any modification to coverable code.

[ewjoachim]

/e2e

[ewjoachim]

Note, this doesn't address the monorepo docs. I wasn't 100% sure if it should also be updated since the configuration looked a bit older (checkout was using < v4). I'm happy to make edits as needed or to pass this off.

Woops. You don't have to update it as part of this PR as it's unrelated but you're right, we should have a look at it.

Thanks for the PR :)

[tim-schilling]

Glad to help where I can! Thanks for maintaining this, it's really helpful on projects.