CI: Introduce ci:normal label

[valentinpalkovic]

Closes #23278

What I did

I have introduced the ci:normal label, which has to be applied to PRs to trigger a normal CircleCI run with a basic set of sandboxes.

How to test

• apply the labels ci:daily, ci:merged and ci:normal one after another on this pr and see, whether the appropriate circleci job is started (I think this does not work, since the github action file is take from next instead of this branch)
• not applying any of the labels will let Danger.js fail, saying, that one of them has to be applied

Checklist

• Make sure your changes are tested (stories and/or unit, integration, or end-to-end tests)
• Make sure to add/update documentation regarding your changes
• If you are deprecating/removing a feature, make sure to update
  MIGRATION.MD

Maintainers

• When this PR is ready for testing, make sure to add ci:normal, ci:merged or ci:daily GH label to it to run a specific set of sandboxes. The particular set of sandboxes can be found in code/lib/cli/src/sandbox-templates.ts
• Make sure this PR contains one of the labels below.

["cleanup", "BREAKING CHANGE", "feature request", "bug", "documentation", "maintenance", "dependencies", "other"]

[JReinhold]

Overall looks good. I'd be comfortable if @yannbf reviewed this, I think he did most of the initial work here.

[valentinpalkovic]

@yannbf Could you also take a look?

[valentinpalkovic]

@JReinhold Could you take another look?

[valentinpalkovic]

@JReinhold One last review. I think now everything is in place :)

[JReinhold]

Great!

[ndelangen]

@valentinpalkovic I'm guessing this PR is superseded and can be closed?