fix: correct user deletion (#10385) (#10386)

* Ensure all user sessions are cleared

* remove double warning text on user delete

(cherry picked from commit 4794d69687)

Co-authored-by: Matthias Mair <code@mjmair.com>

src/frontend/src/tables/settings/UserTable.tsx

@@ -358,6 +358,7 @@ export function UserTable({
     title: t`Delete user`,
     successMessage: t`User deleted`,
     table: table,
+    preFormContent: <></>,
     preFormWarning: t`Are you sure you want to delete this user?`
   });