UserAccessTokenStore migration (#15029)

* Migration completed

* Suggestions

* Fix no new var

* Fix another no new var in the left side

app/user.go

@@ -1457,7 +1457,7 @@ func (a *App) PermanentDeleteUser(user *model.User) *model.AppError {
 	}
 
 	if err := a.Srv().Store.UserAccessToken().DeleteAllForUser(user.Id); err != nil {
-		return err
+		return model.NewAppError("PermanentDeleteUser", "app.user_access_token.delete.app_error", nil, err.Error(), http.StatusInternalServerError)
 	}
 
 	if err := a.Srv().Store.OAuth().PermanentDeleteAuthDataByUser(user.Id); err != nil {