+ composer version

docker-compose.yml.example

@@ -65,6 +65,7 @@ services:
         - PUID=${WORKSPACE_PUID}
         - PGID=${WORKSPACE_PGID}
         - TZ=${WORKSPACE_TIMEZONE}
+        - COMPOSER_VERSION=${WORKSPACE_COMPOSER_VERSION}
         - COMPOSER_GLOBAL_INSTALL=${WORKSPACE_COMPOSER_GLOBAL_INSTALL}
         - COMPOSER_AUTH=${WORKSPACE_COMPOSER_AUTH}
         - COMPOSER_REPO_PACKAGIST=${WORKSPACE_COMPOSER_REPO_PACKAGIST}