Bug: Branch pushes intermittently fail to trigger pipelines with "Reference not found" error

Summary

Pipeline triggering fails intermittently with "Reference not found" error in Git::BranchHooksService for branch pushes.

Ref: Customer support ticket (internal)

What is the current bug behavior?

• Pipelines randomly fail to trigger when pushing to branches (5-10 times per day reported by customer)
• Sidekiq logs show Git::BranchHooksService throwing "Error creating pipeline" with "Reference not found" errors
• Error occurs even when the branch reference clearly exists in the repository
• Teams must manually push "null" changes to trigger pipelines as a workaround
• Issue appears to be related to cache invalidation problems similar to issue #539287, but affects a different component in the pipeline creation process
• Affects Self-Managed instances under normal load conditions

What is the expected correct behavior?

• Pipelines should trigger consistently when pushing commits to branches
• Git references should be properly found and validated during pipeline creation process
• Cache invalidation should not prevent pipeline triggering for valid branch references
• No manual intervention should be required to trigger pipelines for legitimate pushes

Relevant logs and/or screenshots

Customer support ticket (internal)