🎩 What? Why?

This PR makes some changes on system interface:

• Adds a task to create new system admins which prompts asking an email, a password and a password confirmation
• When a system admin signs in if there are no organizations yet the application redirects to the new organization form
• Changes the new/edit organization form to hide some not mandatory advanced settings
• Changes the system dashboard to show an index with the existing organizations
• Adds some tests

📌 Related Issues

• Fixes Improve on-boarding as implementer #7728

📋 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

Please add screenshots of the changes you're proposing

♥️ Thank you!