add config flag to allow single run

Signed-off-by: Stephen Coady <scoady@redhat.com>

roles/openshift-apps/monitor-gating/templates/runner.cfg

@@ -4,6 +4,10 @@ delay = 3600
 # Time between two blocked runs in second
 delay_when_failing = 43200
 
+# Setting the below to true will cancel the scheduler. This means the tests will only run once.
+# NOTE: should never be true in production.
+single_run = false
+
 # blocker issue tags, issue has to have all of them
 {% if env == 'staging' %}
 kb_principal = "monitor-gating/os-master01.stg.iad2.fedoraproject.org@STG.FEDORAPROJECT.ORG"