Update `Admin` -> `Group` -> `Edit` layout to be Pajamas compliant

The Admin -> Group -> Edit layout is not consistent with the Pajamas designs system. We should update this to be compliant with Pajamas.

Availability and Testing

There are several QA tests that use components used by this page, for example:

• app/views/shared/_allow_request_access.html.haml
  • data: { qa_selector: 'request_access_checkbox' }
• app/views/shared/_group_form.html.haml
  • data: { qa_selector: 'group_name_field' }
  • data: { qa_selector: 'group_path_field' }
• app/views/shared/_visibility_radios.html.haml
  • data: { qa_selector: "#{visibility_level_label(level).downcase}_radio" }
• app/views/admin/groups/_form.html.haml
  • data: { qa_selector: 'save_changes_button' }

Please run package-and-qa job to ensure no regressions occur once MR is ready