Keeping the file around while gzipping

Change-Id: I0bd5591f6b02cb2f860b63943768cd126a53a70e
diff --git a/jjb/pipeline/voltha/master/periodic-bbsim-tests.groovy b/jjb/pipeline/voltha/master/periodic-bbsim-tests.groovy
index e0a0871..82a27ec 100755
--- a/jjb/pipeline/voltha/master/periodic-bbsim-tests.groovy
+++ b/jjb/pipeline/voltha/master/periodic-bbsim-tests.groovy
@@ -90,7 +90,7 @@
             done
           fi
           cd $WORKSPACE/${testTarget}-components/
-          gzip onos-voltha-startup-combined.log
+          gzip -k onos-voltha-startup-combined.log
           rm onos-voltha-startup-combined.log
         """
       }
@@ -131,7 +131,7 @@
         done
       fi
       cd $WORKSPACE/${testTarget}-components/
-      gzip onos-voltha-combined.log
+      gzip -k onos-voltha-combined.log
       rm onos-voltha-combined.log
     """
     getPodsInfo("$WORKSPACE/${testTarget}-components")