fix: cache lookup failed with plpgsql_check

[steve-chavez]

Edit: further corrected on #131

Related to supabase/postgres#1502 (comment)

This reproduces a strange bug:

create table storage_stuff();
ERROR:  cache lookup failed for function 0

-- See https://github.com/supabase/supautils/actions/runs/14163088034/job/39671624308?pr=129

That happens when:

• share_preload_libraries=plpgsql_check

• session_preload_libraries=supautils (it doesn't happen when it's on shared_preload_libraries)

• skipping event triggers is done on

  supautils/src/supautils.c

  Lines 105 to 107 in 249a833

  	// we can't skip execution directly inside the fmgr_hook (although we can abort it with ereport)
  	// so instead we use the workaround of changing the event trigger function to a noop function
  	force_noop(flinfo);

  • the root cause is that plpgsql_check caches the InvalidOid used inside the force_noop.

[coveralls]

Pull Request Test Coverage Report for Build 14163228823

Details

• 1 of 1 (100.0%) changed or added relevant line in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 87.047%

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Totals
Change from base Build 13974909065:	0.0%
Covered Lines:	961
Relevant Lines:	1104

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💛 - Coveralls