pgsql: Remove PGSSLCRLDIR from the list of variables ignored in TAP tes

Remove PGSSLCRLDIR from the list of variables ignored in TAP tests

This variable was present in the list added by 9d660670, but it is not
supported by this branch. Issue noticed while diving into a similar
change for pg_regress.c.

Backpatch-through: 9.6

Branch
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REL9_6_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/a78edd4b4207627bcbe5d6d6df604aea480d4326

Modified Files
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src/test/perl/TestLib.pm | 1 -
1 file changed, 1 deletion(-)