We had recent bug report about a possible regression related to
affinity policy enforcement with parallel server create requests.
It turned out not to be a regression but because of the complexity
around affinity enforcement, it might help to add a section to the
compute troubleshooting doc about it which we could refer to in the
future.
Related-Bug: #1863190
Change-Id: I508c48183a7205d46e13154d4e92d31dfa7f7d78