Do not run all system test VMs on MQ (#11946)

Do not run all system test VMs on MQ

Co-authored-by: sarah.chen <sarah.chen@datadoghq.com>

Author: sarahchen6

.gitlab-ci.yml

@@ -88,9 +88,6 @@ workflow:
     - if: '$CI_COMMIT_BRANCH =~ /^v[0-9]+\.[0-9]+\.[0-9]+$/'
       auto_cancel:
         on_new_commit: none
-    - if: '$CI_COMMIT_BRANCH =~ /^mq-working-branch-/'
-      variables:
-        SYSTEM_TESTS_RUN_ALL_VMS: "true"
     - when: always
 
 .test_matrix: &test_matrix