[COMMITTERS] pgsql: Use a better way of skipping all subscription tests on Windows

Use a better way of skipping all subscription tests on Windows

This way we only need to specify the number of tests in one place, and
the output is also less verbose.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/8d9f06097714ce1f4243329172f73c2d20b896a6

Modified Files
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src/test/authentication/t/001_password.pl |  68 ++++++++++---------
src/test/authentication/t/002_saslprep.pl | 105 +++++++++++++++---------------
2 files changed, 90 insertions(+), 83 deletions(-)