Add Dependabot config file

[petechd]

What is the context of this PR?

This adds config of Dependabot for Runner so we can group packages updates into single PRs and ignore specific ones. Check the config documentation

How to review

Follow this guide: https://docs.github.com/en/code-security/getting-started/dependabot-quickstart-guide#prerequisites. Fork https://github.com/dependabot/demo add dependabot.yaml with some config and enable dependabot.

Checklist

• New static content marked up for translation
• Newly defined schema content included in eq-translations repo

[VirajP1002]

Would python-snappy be either a dev or prod dependency? In my fork, it separates the prod and dev dependencies as expected but there's one additional PR addressing python-snappy

[petechd]

Would python-snappy be either a dev or prod dependency? In my fork, it separates the prod and dev dependencies as expected but there's one additional PR addressing python-snappy

Well spotted! I've added a wildcard (seems like I missed it when creating this config) so anything python will be grouped in prod dependencies, since python-snappy is in prod deps.

[VirajP1002]

I created a fork, and the dependabot is correctly organising the dependencies into dev or prod groups, LGTM 👍