Redirect active_sessions to /-/user_settings/active_sessions

What does this MR do and why?

Move /-/profile/active_sessions to /-/user_settings/active_sessions and redirect end_point to new endpoint till the next major release (17.0)

Related to #422478 (closed)

How to set up and validate locally

1. In your local GitLab instance, navigate to the following URL:

http://localhost:3000/-/profile/active_sessions

2. You will be redirected to the new endpoint:

http://localhost:3000/-/user_settings/active_sessions

3. Verify that the active_sessions is displayed correctly.

Numbered steps to set up and validate the change are strongly suggested.

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.