Emit event only once
Emit event only once

When finishReconcileUpdateEmitEvents was introduced in PR #2805,
I forgot to remove one of the original event.Emit, so one event
was sent twice. The fake recorder sometimes probably recognised
the duplicate and filtered it out, causing flackiness in tests,
as unit tests expect a fixed number of events.

Thanks @GregDritschler for troubleshooting this!

Fixes: #2857

tektoncd/pipeline,tektoncd/pipeline