pgsql: Skip pg_baseback long filename test if path too long on Windows

Skip pg_baseback long filename test if path too long on Windows

On Windows, it's sometimes difficult to create a file with a path longer
than 255 chars, and if it can be created it might not be seen by the
archiver. This can be triggered by the test for tar backups with
filenames greater than 100 bytes. So we skip that test if the path would
exceed 255.

Backpatch to all live branches.

Reviewed by Daniel Gustafsson

Discussion: https://postgr.es/m/666ac55b-3400-fb2c-2cea-0281bf36a53c@dunslane.net

Branch
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REL_15_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/c0cb12f9e7b33bbcd64cc93d0811bc10e17e5452

Modified Files
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src/bin/pg_basebackup/t/010_pg_basebackup.pl | 28 +++++++++++++++-------------
1 file changed, 15 insertions(+), 13 deletions(-)