pgsql: doc: warn of SECURITY DEFINER schemas for non-sql_body functions

doc: warn of SECURITY DEFINER schemas for non-sql_body functions

Non-sql_body functions are evaluated at runtime.

Reported-by: Erki Eessaar

Discussion: https://postgr.es/m/AM9PR01MB8268BF5E74E119828251FD34FE409@AM9PR01MB8268.eurprd01.prod.exchangelabs.com

Backpatch-through: 10

Branch
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REL_12_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/8bd054a4c3108222b1d0996bc988ec393358e20c

Modified Files
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doc/src/sgml/ref/create_function.sgml | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)