API issues - minor cleanup of permission check

Adds `set_issue_updated_at` similar to `set_issue_created_at`
permission and cleans up the related permission check in issues
API.

app/policies/project_policy.rb

@@ -164,6 +164,7 @@ class ProjectPolicy < BasePolicy
 
     enable :set_issue_iid
     enable :set_issue_created_at
+    enable :set_issue_updated_at
     enable :set_note_created_at
   end
 

lib/api/issues.rb

@@ -252,14 +252,9 @@ module API
         issue = user_project.issues.find_by!(iid: params.delete(:issue_iid))
         authorize! :update_issue, issue
 
-        # Setting updated_at only allowed for admins and owners as well
-        if params[:updated_at].present?
-          if current_user.admin? || user_project.owner == current_user || current_user.owned_groups.include?(user_project.owner)
-            issue.system_note_timestamp = params[:updated_at]
-          else
-            params.delete(:updated_at)
-          end
-        end
+        # Setting updated_at is allowed only for admins and owners
+        params.delete(:updated_at) unless current_user.can?(:set_issue_updated_at, user_project)
+        issue.system_note_timestamp = params[:updated_at]
 
         update_params = declared_params(include_missing: false).merge(request: request, api: true)
 

spec/policies/project_policy_spec.rb

@@ -66,7 +66,7 @@ describe ProjectPolicy do
     %i[
       change_namespace change_visibility_level rename_project remove_project
       archive_project remove_fork_project destroy_merge_request destroy_issue
-      set_issue_iid set_issue_created_at set_note_created_at
+      set_issue_iid set_issue_created_at set_issue_updated_at set_note_created_at
     ]
   end
 

spec/support/shared_contexts/policies/project_policy_shared_context.rb

@@ -64,7 +64,7 @@ RSpec.shared_context 'ProjectPolicy context' do
     %i[
       change_namespace change_visibility_level rename_project remove_project
       archive_project remove_fork_project destroy_merge_request destroy_issue
-      set_issue_iid set_issue_created_at set_note_created_at
+      set_issue_iid set_issue_created_at set_issue_updated_at set_note_created_at
     ]
   end