Added missing mike config

Author: rbo

mkdocs.yml

@@ -99,6 +99,8 @@ plugins:
       tooltips: false   # control if tooltips will be shown (default: true)
       edit: false       # control if edit button will be shown in the lightbox view (default: true)
       border: 0         # increase or decrease the border / margin around your diagrams (default: 5)
+  - mike:
+      deploy_prefix: preview
 
 hooks:
   - hooks/sha256_filter.py