Update .drone.yml

.drone.yml

@@ -39,8 +39,10 @@ steps:
   - name: deploy
     image: docker/compose
     environment:
-      DOCKER_REG_USERNAME: docker_reg_username
-      DOCKER_REG_PASSWORD: docker_reg_password
+      DOCKER_REG_USERNAME: 
+        from_secret: docker_reg_username
+      DOCKER_REG_PASSWORD: 
+        from_secret: docker_reg_password
     volumes:
       - name: dockersock
         path: /var/run/docker.sock