Backport/scopes drag and drop

[Stef-Rousset]

🎩 Description

The aim of this PR is to add the drag and drop to scopes in decidim-app 0.29, by backporting the content of OpenSourcePolitics/decidim-app#632

📌 Related Issues

• Odoo card https://opensourcepolitics.odoo.com/odoo/all-tasks/3857

Testing

• Log in as admin
• Access Backoffice
• Go to settings
• Access to scopes
• Check that you can sort (sort and refresh to make sure everything stays in place)
• Access onto a scope and try to sort the subscopes (same tests as above)
• Go to a process and activate the scopes on a proposals component
• Check the pages that we quoted above and check that everything is well sorted
• You can repeat the process multiple times to check that it's always sorted correctly