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_11_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/2e99ce68bcd22d41d417cdd05ccd47d54c30a2a0

Modified Files
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src/bin/pg_basebackup/t/010_pg_basebackup.pl | 24 +++++++++++++++---------
1 file changed, 15 insertions(+), 9 deletions(-)