Merge pull request #8175 from anaethoss/patch-1

fix example typo for Schema.prototype.plugin()

lib/schema.js

@@ -1378,7 +1378,7 @@ Schema.prototype.post = function(name) {
  *
  *     const s = new Schema({ name: String });
  *     s.plugin(schema => console.log(schema.path('name').path));
- *     mongoose.model('Test', schema); // Prints 'name'
+ *     mongoose.model('Test', s); // Prints 'name'
  *
  * @param {Function} plugin callback
  * @param {Object} [opts]