b85a9d046e introduced a new RelIdToTypeIdCacheHash, whose entries should
exist for typecache entries with TCFLAGS_HAVE_PG_TYPE_DATA flag set or any
of TCFLAGS_OPERATOR_FLAGS set or tupDesc set. However, TypeCacheOpcCallback(),
which resets TCFLAGS_OPERATOR_FLAGS, was forgotten to update
RelIdToTypeIdCacheHash.
This commit adds a delete_rel_type_cache_if_needed() call to the
TypeCacheOpcCallback() function to maintain RelIdToTypeIdCacheHash after
resetting TCFLAGS_OPERATOR_FLAGS.
Also, this commit fixes the name of the delete_rel_type_cache_if_needed()
function in its mentions in the comments.
Reported-by: Noah Misch
Discussion: https://postgr.es/m/20250411203241.e9.nmisch%40google.com
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