override stage_archive when running stage_4

Signed-off-by: Michael Marchetti <mmarchetti@sandvine.com>
diff --git a/jenkins/ci-pipelines/ci_stage_3.groovy b/jenkins/ci-pipelines/ci_stage_3.groovy
index ce3aef6..724daad 100644
--- a/jenkins/ci-pipelines/ci_stage_3.groovy
+++ b/jenkins/ci-pipelines/ci_stage_3.groovy
@@ -256,6 +256,8 @@
             }
 
             if ( params.DO_STAGE_4 ) {
+                // override stage_archive to only archive on stable
+                stage_archive = false
                 stage("stage_4") {
                     run_systest(container_name,container_name,"openstack_stage_4",params.HIVE_VIM_1)