Drop legacy plugins

book.json

@@ -7,30 +7,6 @@
       "GitHub": "https://github.com/yeasy/docker_practice"
     }
   },
-  "plugins": [
-    "-livereload",
-    "mermaid-gb3",
-    "github",
-    "page-treeview",
-    "editlink"
-  ],
-  "pluginsConfig": {
-    "mermaid-gb3": {
-      "theme": "default"
-    },
-    "github": {
-      "url": "https://github.com/yeasy/docker_practice"
-    },
-    "editlink": {
-      "base": "https://github.com/yeasy/docker_practice/blob/master/",
-      "label": "编辑本页"
-    },
-    "page-treeview": {
-      "copyright": "Copyright © yeasy",
-      "minHeaderCount": "2",
-      "minHeaderDeep": "2"
-    }
-  },
   "pdf": {
     "pageNumbers": true,
     "fontSize": 12,