Clarify that the name in LDAP is synced

What does this MR do?

This MR adds an entry to the docs to clarify that the name field in LDAP sync is synchronized. It also adds a note to inform users that the name field is not synchronized if the Prevent users from changing their profile name checkbox in Admin > Settings > General > Account and Limit is checked.

This came up when I was working on this internal ticket.

Related issues

• "Prevent users from changing their profile name" setting should not affect LDAP sync profile name updates

Author's checklist

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Reviewer's checklist

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