`mongoose.model() --> mongoose.model()

MD link format fixed

Author: amar9312

docs/middleware.pug

@@ -261,7 +261,7 @@ block content
     ```
 
     This means that you must add all middleware and [plugins](/docs/plugins.html)
-    **before** calling [`mongoose.model()](/docs/api/mongoose.html#mongoose_Mongoose-model).
+    **before** calling [mongoose.model()](/docs/api/mongoose.html#mongoose_Mongoose-model).
     The below script will print out "Hello from pre save":
 
     ```javascript