Update .drone.yml

Reviewed-on: mephisto/clubbing-content#30

.drone.yml

@@ -34,8 +34,11 @@ steps:
         from_secret: KNOWN_HOST
   - name: run hugo
     image: appleboy/drone-ssh
-    secrets: [ HUGO_ROOT ]
+    environment:
+      HUGO_ROOT:
+        from_secret: HUGO_ROOT
     settings:
+      envs: [ HUGO_ROOT ]
       host: 
         from_secret: SSH_HOST
       username: 
@@ -46,7 +49,7 @@ steps:
       known_hosts:
         from_secret: KNOWN_HOST
       script:
-        - cd $${HUGO_ROOT}
+        - cd $HUGO_ROOT
         - hugo
 
 trigger: