Add RETIREMENT_STATES to edxapp to make retirement workflow configurable (#4513)

CHANGELOG.md

+- Role: edxapp
+  - Added `RETIREMENT_STATES` to generic_env_config to support making the retirement workflow configurable.
+
 - Removed Vagrantfiles for devstack and fullstack, and supporting files.
 
 - Role: xqueue

playbooks/roles/edxapp/defaults/main.yml

@@ -731,6 +731,13 @@ EDXAPP_RETIRED_USER_SALTS:
   - "OVERRIDE ME WITH A RANDOM VALUE"
   - "ROTATE SALTS BY APPENDING NEW VALUES"
 EDXAPP_RETIREMENT_SERVICE_WORKER_USERNAME: "OVERRIDE THIS WITH A VALID LMS USERNAME"
+# These get loaded into database models per environment via management command
+# These are the required states, environmental overrides are in edx-internal.
+EDXAPP_RETIREMENT_STATES:
+  - "PENDING"
+  - "ERRORED"
+  - "ABORTED"
+  - "COMPLETE"
 
 # Comprehensive Theming
 # Deprecated, maintained for backward compatibility
@@ -1248,6 +1255,7 @@ generic_env_config:  &edxapp_generic_env
   RETIRED_EMAIL_DOMAIN: "{{ EDXAPP_RETIRED_EMAIL_DOMAIN }}"
   RETIRED_USER_SALTS: "{{ EDXAPP_RETIRED_USER_SALTS }}"
   RETIREMENT_SERVICE_WORKER_USERNAME: "{{ EDXAPP_RETIREMENT_SERVICE_WORKER_USERNAME }}"
+  RETIREMENT_STATES: "{{ EDXAPP_RETIREMENT_STATES }}"
 
   PASSWORD_MIN_LENGTH: "{{ EDXAPP_PASSWORD_MIN_LENGTH }}"
   PASSWORD_MAX_LENGTH: "{{ EDXAPP_PASSWORD_MAX_LENGTH }}"