Add dependabot group for rubocop* bundler updates

[Copilot]

This PR addresses the issue of managing individual bundler dependency updates for gems matching the pattern "rubocop*" by introducing a dedicated dependabot group configuration.

Problem

Previously, each rubocop-related dependency update (rubocop, rubocop-minitest, rubocop-rake) would generate separate PRs, making it harder to review and merge related updates efficiently.

Solution

Added a new rubocop group to .github/dependabot.yml that bundles all updates for dependencies matching the pattern "rubocop*" into a single PR.

Changes

• Updated .github/dependabot.yml to include a new group:

  groups:
    rubocop:
      patterns:
        - "rubocop*"
      dependency-type: "development"

Benefits

• Reduced review overhead: All rubocop-related updates are now consolidated into single PRs
• Improved efficiency: Easier to review and merge related dependency changes together
• Better organization: Groups logically related gems (rubocop, rubocop-minitest, rubocop-rake)

The configuration follows the existing file structure and is consistent with other dependency groups already defined in the project. This change will take effect on the next dependabot run.

Fixes #[issue_number]

Fixes #23

Fixes #23

---

💬 Share your feedback on Copilot coding agent for the chance to win a $200 gift card! Click here to start the survey.

[markhallen]

@copilot We have a dependabot config error:

Your .github/dependabot.yml contained invalid details
Dependabot encountered the following error when parsing your .github/dependabot.yml:

The property '#/updates/0/groups/rubocop/dependency-type' value "direct" did not match one of the following values: production, development
Please update the config file to conform with Dependabot's specification.

Details
For more info on the config file format, see [the config file documentation](https://docs.github.com/en/github/administering-a-repository/configuration-options-for-dependency-updates#configuration-options-for-dependabotyml)

[Copilot]

@copilot We have a dependabot config error:

...

Fixed the dependabot configuration error in commit 4c21b1c. The issue was that dependency-type: "direct" is not a valid value according to the dependabot specification. The valid values are only "production" or "development". Since rubocop gems are development dependencies in this project, I changed it to dependency-type: "development".