pgsql: Stabilize output of new regression test.

Stabilize output of new regression test.

Per buildfarm, the output order of \dx+ isn't consistent across
locales.  Apply NO_LOCALE to force C locale.  There might be a
more localized way, but I'm not seeing it offhand, and anyway
there is nothing in this test module that particularly cares
about locales.

Security: CVE-2022-2625

Branch
------
REL_12_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/dfab37100de1127595b4f1f6949137bfea355c22

Modified Files
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src/test/modules/test_extensions/Makefile | 3 +++
1 file changed, 3 insertions(+)