fix drone meta again

.drone.yml

@@ -2,8 +2,7 @@ pipeline:
   modify_staging:
     image: debian:stretch
     commands:
-      - ls -lha
-      - mv content/_meta-staging.mds content/_meta.md
+      - mv content/_meta-staging.md content/_meta.md
       - mv config/config-staging.yml config/config.yml
 
   deploy_staging: