docs: add missing require to example code

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type: pre_commit_static_analysis_report
description: Results of running static analysis checks when committing changes.
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    status: passed
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---

Author: Planeshifter

lib/node_modules/@stdlib/_tools/remark/plugins/remark-lint-expected-html-sections/README.md

@@ -59,6 +59,8 @@ function done( error, file ) {
 The plugin can be configured with a custom schema that defines required and optional sections.
 
 ```javascript
+var remark = require( 'remark' );
+
 var opts = {
     'schema': {
         'root': {