Add triggers to Duo Code Review foundational flow

Context

Follow-up to !216090 - Automatic Flow triggers for foundational flows

Problem

The Duo Code Review foundational flow has its own triggering mechanism (see https://gitlab.com/gitlab-org/gitlab/-/blob/7355bea2d76588e56dc21c631b8b35eb790e044c/ee/app/services/ee/merge_requests/base_service.rb#L71-86) that is separate from the generic flow trigger system configured by !216090.

Currently, the custom trigger execution in the flow trigger system doesn't account for the Duo Code Review flow's existing triggering logic.

Solution

The custom trigger for Duo Code Review should be executed only if there are no trigger flows configured. This prevents duplicate triggering and respects the existing triggering mechanism.

Related

• Automatic Flow triggers for foundational flows (!216090)
• Automatically create triggers for foundational ... (#583191)