pgsql: Fix missing regex slash that caused perltidy to get confused on

Fix missing regex slash that caused perltidy to get confused on
copyright.pl.

Backpatch to 9.2.

Branch
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REL9_2_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/071589cb3f6b4e259d3b87f228fd1c69b8189037

Modified Files
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src/tools/copyright.pl | 16 ++++++++--------
1 files changed, 8 insertions(+), 8 deletions(-)