Resolve "Allow self-managed to deactivate users after 90 days"

app/models/user.rb

@@ -69,7 +69,7 @@ class User < ApplicationRecord
   LOGIN_FORBIDDEN = "Your account does not have the required permission to login. Please contact your GitLab " \
                     "administrator if you think this is an error."
 
-  MINIMUM_INACTIVE_DAYS = 180
+  MINIMUM_INACTIVE_DAYS = 90
 
   # Override Devise::Models::Trackable#update_tracked_fields!
   # to limit database writes to at most once every hour

changelogs/unreleased/42989-update-deactivation-threshold-to-90-days.yml

+---
+title: Adjusted deactivation threshold from 180 to 90 days
+merge_request: 42989
+author:
+type: changed

doc/user/admin_area/activating_deactivating_users.md

@@ -39,7 +39,7 @@ A user can be deactivated from the Admin Area. To do this:
 Please note that for the deactivation option to be visible to an admin, the user:
 
 - Must be currently active.
-- Must not have signed in, or have any activity, in the last 180 days.
+- Must not have signed in, or have any activity, in the last 90 days.
 
 Users can also be deactivated using the [GitLab API](../../api/users.md#deactivate-user).