pgsql: Fix timezone dependence in test_misc/012_ddlutils.pl

Fix timezone dependence in test_misc/012_ddlutils.pl

The tests introduced in c529ee38b9e are timezone sensitive.

Pin the cluster's timezone to UTC at init time so timestamptz output
is deterministic regardless of the host's local timezone.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/df1bac400fb4877ba9f4bda2a29adaf8b40b4bd3

Modified Files
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src/test/modules/test_misc/t/012_ddlutils.pl | 3 +++
1 file changed, 3 insertions(+)