User Control Panel improvements

[erral]

fixes #4551 and #4018

This PR contains the following functionalities identified in #4551:

• Show the username next to the fullname in the user controlpanel
• Don't show the user table headings when many_users setting is true and no search have been made.
• Show "no results found" when doing a search in the user controlpanel and there are no results.
• Don't show the group table headings when many_groups setting is true and no search have been made.
• Show "no results found" when doing a search in the group controlpanel and there are no results.

And the following identifed in #4018

• Add a button to Edit the user data in a ModalForm following the userschema configured in the back-end

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[cypress]

Passing run #7159 ↗︎

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Details:

Merge branch 'master' into erral-user-controlpanel
Project: Volto	Commit: 8dd8ee40d7
Status: Passed	Duration: 15:35 💡
Started: Sep 11, 2023 5:34 PM	Ended: Sep 11, 2023 5:49 PM

_{This comment has been generated by cypress-bot as a result of this project's GitHub integration settings.}

[wesleybl]

Show "no results found" when doing a search in the user controlpanel and there are no results.
Show "no results found" when doing a search in the group controlpanel and there are no results.

I see the string "undefined" instead of "no results found"

I think this PR still doesn't close #4018. I would expect all field names and descriptions to come from the backend. But this can be done in another PR.

[erral]

Show "no results found" when doing a search in the user controlpanel and there are no results.
Show "no results found" when doing a search in the group controlpanel and there are no results.

I see the string "undefined" instead of "no results found"

Ups, I will check it.

I think this PR still doesn't close #4018. I would expect all field names and descriptions to come from the backend. But this can be done in another PR.

The username, password, roles and groups fields of the edit form are not part of the userschema, so we need something else in the REST API to handle them in the back-end.

[ksuess]

The change of user data should trigger an update of the list of users.

[nileshgulia1]

I am eagerly anticipating the merger!

[erral]

If you need me to review something, I will be off until at least 11th of August