fix MAX_FAIL/RERUNS_RETRY warnings

Change-Id: I1a81e9c92cf3d112c58f91567550934ec20f3bc7
Reviewed-on: https://gerrit.instructure.com/c/canvas-lms/+/213843
Reviewed-by: Robert Lamb <rlamb@instructure.com>
Tested-by: Jenkins
Product-Review: Cameron Matheson <cameron@instructure.com>
QA-Review: Cameron Matheson <cameron@instructure.com>

docker-compose.new-jenkins.yml

@@ -16,8 +16,8 @@ services:
       RAILS_DB_PASSWORD: ''
       DATABASE_URL: "postgres://postgres@postgres:5432/canvas_test"
       RANDOMIZE_SEQUENCES: 1
-      RERUNS_RETRY: $RERUNS_RETRY
-      MAX_FAIL: $MAX_FAIL
+      RERUNS_RETRY:
+      MAX_FAIL:
 
   redis:
     image: starlord.inscloudgate.net/jenkins/redis:alpine