pgsql: Minor style improvements for tab-completion test.

Minor style improvements for tab-completion test.

Use qr// syntax for regex values.
Include the regex that failed to match in diagnostic reports.

Dagfinn Ilmari Mannsåker

Discussion: https://postgr.es/m/87k16610xk.fsf@wibble.ilmari.org

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/8c081a2f4e8eec11747e709c1ea4c3485ef129dd

Modified Files
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src/bin/psql/t/010_tab_completion.pl | 27 +++++++++++++++------------
1 file changed, 15 insertions(+), 12 deletions(-)