Add initial dependabot configuration

[caxu-rh]

This should cover just the GitHub Actions usage for now. Leaving Golang modules out for now since those updates need to be scheduled/timed specifically.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Enterprise

Run ID: ba049bb5-a1af-4f54-9517-7e25810213fe

📥 Commits

Reviewing files that changed from the base of the PR and between e21ac64 and cc91bbb.

📒 Files selected for processing (1)

• .github/dependabot.yml

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📝 Walkthrough

Summary by CodeRabbit

• Chores
  • Updated automated dependency management configuration for GitHub Actions.

Walkthrough

Dependabot configuration is added to automate GitHub Actions dependency updates on a weekly schedule with a 7-day cooldown between update attempts, enabling continuous dependency maintenance for the repository's workflow actions.

Changes

Dependabot Configuration

Layer / File(s)	Summary
Dependabot configuration for GitHub Actions .github/dependabot.yml	Dependabot configuration file enables automated GitHub Actions dependency updates for the root directory on a weekly interval with a 7-day cooldown between update attempts.

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~2 minutes

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title 'Add initial dependabot configuration' accurately reflects the main change: adding a new Dependabot configuration file to the repository.
Description check	✅ Passed	The description clearly relates to the changeset, explaining that Dependabot is configured for GitHub Actions only, with Golang modules intentionally excluded for later consideration.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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_{Comment @coderabbitai help to get the list of available commands and usage tips.}