Remove platform name from credentials playbook

CHANGELOG.md

+- Role: credentials
+  - Removed `CREDENTIALS_PLATFORM_NAME` from credentials playbook
 - Role: common
   - Renamed `COMMON_AWS_SYNC` to `COMMON_OBJECT_STORE_LOG_SYNC`
   - Renamed `COMMON_AWS_SYNC_BUCKET` to `COMMON_OBJECT_STORE_LOG_SYNC_BUCKET`

playbooks/roles/credentials/defaults/main.yml

@@ -61,8 +61,6 @@ CREDENTIALS_SOCIAL_AUTH_EDX_OIDC_KEY: 'SET-ME-TO-A-UNIQUE-LONG-RANDOM-STRING'
 CREDENTIALS_SOCIAL_AUTH_EDX_OIDC_SECRET: 'SET-ME-TO-A-UNIQUE-LONG-RANDOM-STRING'
 CREDENTIALS_SOCIAL_AUTH_REDIRECT_IS_HTTPS: false
 
-CREDENTIALS_PLATFORM_NAME: 'Your Platform Name Here'
-
 # credentials service user in programs service and lms
 CREDENTIALS_SERVICE_USER: 'credentials_service_user'
 
@@ -171,8 +169,6 @@ CREDENTIALS_SERVICE_CONFIG:
   DATABASES: '{{ CREDENTIALS_DATABASES }}'
   CACHES: '{{ CREDENTIALS_CACHES }}'
 
-  PLATFORM_NAME: '{{ CREDENTIALS_PLATFORM_NAME }}'
-
   # Set credentials files storage backend
   FILE_STORAGE_BACKEND: '{{ CREDENTIALS_FILE_STORAGE_BACKEND }}'