pgsql: Fix pg_upgrade to detect non-upgradable anyarray usages.

Fix pg_upgrade to detect non-upgradable anyarray usages.

When we changed some built-in functions to use anycompatiblearray
instead of anyarray, we created a dump/restore hazard for user-defined
operators and aggregates relying on those functions: the user objects
have to be modified to change their signatures similarly. This causes
pg_upgrade to fail partway through if the source installation contains
such objects. We generally try to have pg_upgrade detect such hazards
and fail before it does anything exciting, so add logic to detect
this case too.

Back-patch to v14 where the change was made.

Justin Pryzby, reviewed by Andrey Borodin

Discussion: /messages/by-id/3383880.QJadu78ljV@vejsadalnx

Branch
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REL_15_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/c069f427855a486a4d32d84e2bf4c932df00d7d5

Modified Files
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src/bin/pg_upgrade/check.c | 135 +++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 135 insertions(+)