This reverts merge request !20679

Signed-off-by: Rémy Coutable <remy@rymai.me>

When a user checks the `accept` checkbox, we will track that
acceptance as usual. That way they don't need to accept again after
they complete the registration.

When an unauthenticated user visits the `/-/users/terms` page, there
is no button to accept, decline or continue. The 'current-user menu'
is also hidden from the top bar.

Ensure ApplicationSetting#performance_bar_allowed_group_id is properly set when retrieved from cache

Signed-off-by: Rémy Coutable <remy@rymai.me>

Adds changelog entry, changes RemoteMirror#sync? to be semantically sound and remove reference to pull mirrors in view

This enforces the terms in the web application. These cases are
specced:

- Logging in: When terms are enforced, and a user logs in that has not
  accepted the terms, they are presented with the screen. They get
  directed to their customized root path afterwards.
- Signing up: After signing up, the first screen the user is presented
  with the screen to accept the terms. After they accept they are
  directed to the dashboard.
- While a session is active:
  - For a GET: The user will be directed to the terms page first,
    after they accept the terms, they will be directed to the page
    they were going to
  - For any other request: They are directed to the terms, after they
    accept the terms, they are directed back to the page they came
    from to retry the request. Any information entered would be
    persisted in localstorage and available on the page.

This allows admins to define terms in the application settings.

Every time the terms are adjusted, a new version is stored and becomes
the 'active' version. This allows tracking which specific version was
accepted by a user.

That way we can link a users acceptance of terms directly to a terms record.

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

If form does not have import sources checkboxes we should not reset
import sources to empty. This fixes issue when import sources got reset
after user modifies unrelated settings section like GitLab pages

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Signed-off-by: Rémy Coutable <remy@rymai.me>

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>