default the small bulk email jobs to be sent through the low priority queue

CHANGELOG.md

+- Role: edxapp
+  - Set the default value for EDXAPP_BULK_EMAIL_ROUTING_KEY_SMALL_JOBS to
+ 'edx.lms.core.low'.
+
 - Role: jenkins_master
   - Update pinned use of JDK7 in Jenkins installs to default JDK version from role `oraclejdk`.
 

playbooks/roles/edxapp/defaults/main.yml

@@ -527,6 +527,7 @@ EDXAPP_CELERY_WORKERS:
     monitor: False
     max_tasks_per_child: 1
 EDXAPP_RECALCULATE_GRADES_ROUTING_KEY: 'edx.lms.core.default'
+EDXAPP_BULK_EMAIL_ROUTING_KEY_SMALL_JOBS: 'edx.lms.core.low'
 EDXAPP_LMS_CELERY_QUEUES: "{{ edxapp_workers|selectattr('service_variant', 'equalto', 'lms')|map(attribute='queue')|map('regex_replace', '(.*)', 'edx.lms.core.\\1')|list }}"
 EDXAPP_CMS_CELERY_QUEUES: "{{ edxapp_workers|selectattr('service_variant', 'equalto', 'cms')|map(attribute='queue')|map('regex_replace', '(.*)', 'edx.cms.core.\\1')|list }}"
 
@@ -1137,6 +1138,7 @@ lms_env_config:
   API_DOCUMENTATION_URL: "{{ EDXAPP_API_DOCUMENTATION_URL }}"
   AUTH_DOCUMENTATION_URL: "{{ EDXAPP_AUTH_DOCUMENTATION_URL }}"
   RECALCULATE_GRADES_ROUTING_KEY: "{{ EDXAPP_RECALCULATE_GRADES_ROUTING_KEY }}"
+  BULK_EMAIL_ROUTING_KEY_SMALL_JOBS: "{{ EDXAPP_BULK_EMAIL_ROUTING_KEY_SMALL_JOBS }}"
   CELERY_QUEUES: "{{ EDXAPP_LMS_CELERY_QUEUES }}"
   ALTERNATE_WORKER_QUEUES: "cms"
   ENTERPRISE_COURSE_ENROLLMENT_AUDIT_MODES: "{{ EDXAPP_ENTERPRISE_COURSE_ENROLLMENT_AUDIT_MODES }}"