HPCC-11913 Integrate Performance Testing into nightly build.

Remove quote of output from summary report.

Signed-off-by: Attila Vamos <attila.vamos@gmail.com>
Merge pull request #6422 from AttilaVamos/HPCC-11913-fix

HPCC-11913 Integrate Performance Testing into nightly build.

Reviewed-by: Gavin Halliday <ghalliday@hpccsystems.com>