[COMMITTERS] pgsql: Fix TAP infrastructure to support Mingw better

Fix TAP infrastructure to support Mingw better

archive_command and restore_command need to refer to Windows paths, not
Msys virtual file system paths, as postgres is completely unaware of the
latter, so prefix them with the Windows path to the virtual file system
root. Clean psql output of carriage returns.

Branch
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REL9_6_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/11927e575dd2afc8361e785c34db2141156702d6

Modified Files
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src/test/perl/PostgresNode.pm | 14 ++++++++++++--
1 file changed, 12 insertions(+), 2 deletions(-)