Keep GitHub Actions up to date with GitHub's Dependabot

[cclauss]

Automates the process of creating pull requests like:

• 1147

• 1292

Fixes warnings like at the bottom right of https://github.com/mher/flower/actions/runs/9844246249

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• Keeping your actions up to date with Dependabot

• Configuration options for the dependabot.yml file - package-ecosystem

• Modern pip has a real dependency resolver so give it all requirements at once

• Fix pylint issue https://docs.astral.sh/ruff/rules/yield-in-for-loop

• celery-version: ['5.2.*', '5.3.*', '5.4.*']

• Celery 5.2 does not support Python 3.12

  • https://docs.celeryq.dev/en/stable/history/whatsnew-5.3.html

[cclauss]

Generated

• 1394