get_job_by_platform: use a GROUP BY
get_job_by_platform: use a GROUP BY

Use a GROUP BY to eliminate duplicated row in the output.

Change-Id: I80bb17e36b669daabf4cdf80fed26eb649cd86bc

goneri/dci-control-server,goneri/dci-control-server,enovance/dci-control-server,goneri/dci-control-server,redhat-cip/dci-control-server,enovance/dci-control-server,redhat-cip/dci-control-server,goneri/dci-control-server