Add GitHub actions to the dependabot configuration.

[leander-dsouza]

🎉 New feature

Summary

• Added dependabot configuration to periodically update outdated GitHub actions.

Test it

• Once dependabot is enabled for this repository and this PR is merged, if any outdated GitHub actions exist, dependabot PRs having a prefix of 🛠️ would be created.

Checklist

• Signed all commits for DCO
• Added tests
• Added example and/or tutorial
• Updated documentation (as needed)
• Updated migration guide (as needed)
• Consider updating Python bindings (if the library has them)
• codecheck passed (See contributing)
• All tests passed (See test coverage)
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• Was GenAI used to generate this PR? If so, make sure to add "Generated-by" to your commits. (See this policy for more info.)

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[arjo129]

Seems reasonable enough to me, does any of the PMC object?