Improvements in Process Groups and processes block

[entantoencuanto]

• Fixes a query returning wrong results when current user is admin
• Includes promoted groups in organization homepage highlighted processes:
  • The promoted groups are prioritized over the groups and displayed first
  • If there is only a promoted group it's shown using the same partial used for promoted groups in processes index
• Adds some system tests to homepage to check the block

Note: This PR is built on top of feature/process_groups_improvements-highlighted_groups, the branch of #6828 PR.

📌 Related Issues

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• Related to EPIC: Process Group highlights #6481
• Fixes Highlighted process groups content block in Homepage #6483

Testing

Enable this block in organization homepage

📋 Checklist

🚨 Please review the guidelines for contributing to this repository.

• ❓ CONSIDER adding a unit test if your PR resolves an issue.
• ✔️ DO check open PR's to avoid duplicates.
• ✔️ DO keep pull requests small so they can be easily reviewed.
• ✔️ DO build locally before pushing.
• ✔️ DO make sure tests pass.
• ✔️ DO make sure any new changes are documented in docs/.
• ✔️ DO add and modify seeds if necessary.
• ✔️ DO add CHANGELOG upgrade notes if required.
• ✔️ DO add to GraphQL API if there are new public fields.
• ✔️ DO add link to MetaDecidim if it's a new feature.
• ❌AVOID breaking the continuous integration build.
• ❌AVOID making significant changes to the overall architecture.

📷 Screenshots

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♥️ Thank you!

[tramuntanal]

Can you rebase please with feature/process_groups_improvements-highlighted_groups ? @entantoencuanto