Community contribution MRs get stuck in "The pipeline for this merge request did not complete"

@ohoral first reported this in Slack for !54138 (merged) and I experienced the same in !55671 (merged)

@fabiopitino mentioned that the actual_head_pipeline being checked by the MR widget is referring to the last fork pipeline even though newer pipelines for merged results have been run.

I worked around this by retrying failed jobs in the last fork pipeline so that it goes back into the running state and I can set MWPS.