Remove backticks from slack message

.gitlab/ci/notifications.gitlab-ci.yml

@@ -11,7 +11,7 @@ schedule:package-and-qa:notify-success:
     - .only-canonical-schedules
     - .notify
   script:
-    - 'scripts/notify-slack qa-master ":tada: Scheduled QA against `master` passed! :tada: See $CI_PIPELINE_URL." ci_passing'
+    - 'scripts/notify-slack qa-master ":tada: Scheduled QA against master passed! :tada: See $CI_PIPELINE_URL." ci_passing'
   needs: ["schedule:package-and-qa"]
   when: on_success
 
@@ -20,6 +20,6 @@ schedule:package-and-qa:notify-failure:
     - .only-canonical-schedules
     - .notify
   script:
-    - 'scripts/notify-slack qa-master ":skull_and_crossbones: Scheduled QA against `master` failed! :skull_and_crossbones: See $CI_PIPELINE_URL." ci_failing'
+    - 'scripts/notify-slack qa-master ":skull_and_crossbones: Scheduled QA against master failed! :skull_and_crossbones: See $CI_PIPELINE_URL." ci_failing'
   needs: ["schedule:package-and-qa"]
   when: on_failure