pgsql: Remove portability hazard in unsafe_tests/sql/guc_privs.sql.

Remove portability hazard in unsafe_tests/sql/guc_privs.sql.

This new-in-v15 test case assumed it could set max_stack_depth as high
as 2MB. You might think that'd be true on any modern platform but
you'd be wrong, as I found out while experimenting with NetBSD/hppa.

This test is about privileges not platform capabilities, so there seems
no need to use any value greater than the 100kB setting already used
in a couple of places in the core regression tests. There's certainly
no call to expect people to raise their platform's default ulimit just
to run this test.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/5e5fa323350060360799004f96840bbf3cb51e49

Modified Files
--------------
src/test/modules/unsafe_tests/expected/guc_privs.out | 4 ++--
src/test/modules/unsafe_tests/sql/guc_privs.sql | 4 ++--
2 files changed, 4 insertions(+), 4 deletions(-)