Zipping the combined log and removing it to save jenkins space

Change-Id: I2c663afcb14b0deb9892d7d39e7a556a152e3804
diff --git a/jjb/pipeline/voltha/master/periodic-bbsim-tests.groovy b/jjb/pipeline/voltha/master/periodic-bbsim-tests.groovy
index fb49076..e0a0871 100755
--- a/jjb/pipeline/voltha/master/periodic-bbsim-tests.groovy
+++ b/jjb/pipeline/voltha/master/periodic-bbsim-tests.groovy
@@ -89,6 +89,9 @@
               kill -9 \$P_ID
             done
           fi
+          cd $WORKSPACE/${testTarget}-components/
+          gzip onos-voltha-startup-combined.log
+          rm onos-voltha-startup-combined.log
         """
       }
       sh """
@@ -127,6 +130,9 @@
           kill -9 \$P_ID
         done
       fi
+      cd $WORKSPACE/${testTarget}-components/
+      gzip onos-voltha-combined.log
+      rm onos-voltha-combined.log
     """
     getPodsInfo("$WORKSPACE/${testTarget}-components")
   }