pgbuildfarm - client-code: fix typo in config var name, discovered by

Log Message:
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fix typo in config var name, discovered by DarcyB

Modified Files:
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client-code:
run_build.pl (r1.8 -> r1.9)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pgbuildfarm/client-code/run_build.pl.diff?r1=1.8&r2=1.9)