fix drone

.drone.yml

@@ -2,6 +2,10 @@
 kind: pipeline
 type: docker
 name: build
+
+environment:
+  WIKI_PATH: ${WIKI_PATH}
+
 steps:
 - name: build
   image: squidfunk/mkdocs-material:7.1.9
@@ -19,6 +23,5 @@ volumes:
 - name: site
   host:
     # path: /home/sthope/docker/wiki
-    path: 
-      from_secret: wiki_folder
+    path: ${wiki_folder}