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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REL_13_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/f865d2affc456ede17e46949007682e91d19daa4

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