Rule out hybrid keys in output descriptors #28511

1. 
   darosior commented at 11:37 am on September 20, 2023: member

   @achow101 noted we don’t reject them therefore they must be silently accepted. This is not part of the specs, we should remove them. Also cc @sipa.

   I can take care of this.

2. achow101 closed this on Oct 5, 2023

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