feat: added merge groups

[mfranzke]

Proposed changes

according to https://docs.github.com/en/repositories/configuring-branches-and-merges-in-your-repository/configuring-pull-request-merges/managing-a-merge-queue#triggering-merge-group-checks-with-github-actions

and setting up activating a new ruleset for merge groups, as documented: https://github.com/db-ux-design-system/core-web/settings/rules/3944111

We should additionally have a look at https://github.com/googleapis/release-please as well. we've integrated changesets for release CHANGELOG management.

Types of changes

• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Refactoring (fix on existing components or architectural decisions)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation Update (if none of the other choices apply)

Further comments

🔭🐙🐈 Test this branch here: https://db-ux-design-system.github.io/core-web/review/feat-added-merge-groups

[github-actions]

🔭🐙🐈 Test this branch here: https://db-ux-design-system.github.io/core-web/review/feat-added-merge-groups

[Copilot]

Pull Request Overview

This PR adds GitHub merge group support to CI/CD workflows to enable merge queue functionality. The changes configure workflows to trigger on merge group events in addition to existing pull request triggers, supporting GitHub's merge queue feature for better branch protection.

• Adds merge_group triggers to three GitHub Actions workflow files
• Configures merge group events to target the "main" branch consistently
• Enables CI checks to run on merge groups as documented in GitHub's merge queue guidance

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
.github/workflows/pull-request.yml	Added merge group trigger for main branch
.github/workflows/pull-request-opened.yml	Added merge group trigger for main branch
.github/workflows/default.yml	Added merge group trigger without branch specification

[Copilot]

The merge_group trigger should specify branches for consistency with the other workflow files. Consider adding 'branches: ["main"]' to match the pattern used in pull-request.yml and pull-request-opened.yml.

Suggested change

	merge_group:
	merge_group:
	branches:
	- "main"

[changeset-bot]

⚠️ No Changeset found

Latest commit: 264431d

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