Include custom rule markdownlint-rule-github-internal-links when validating project Markdown files.

README.md

@@ -865,7 +865,7 @@ const results = window.markdownlint.sync(options).toString();
 ## Examples
 
 For ideas how to integrate `markdownlint` into your workflow, refer to the
-following projects or one of the tools in the [Related section](#Related):
+following projects or one of the tools in the [Related section](#related):
 
 * [.NET Documentation](https://docs.microsoft.com/en-us/dotnet/) ([Search repository](https://github.com/dotnet/docs/search?q=markdownlint))
 * [ally.js](https://allyjs.io/) ([Search repository](https://github.com/medialize/ally.js/search?q=markdownlint))

package.json

@@ -62,6 +62,7 @@
     "markdown-it-sub": "~1.0.0",
     "markdown-it-sup": "~1.0.0",
     "markdown-it-texmath": "~0.9.7",
+    "markdownlint-rule-github-internal-links": "~0.1.0",
     "markdownlint-rule-helpers": "~0.15.0",
     "npm-run-all": "~4.1.5",
     "strip-json-comments": "~3.1.1",

test/markdownlint-test.js

@@ -84,11 +84,12 @@ test.cb("projectFilesNoInlineConfig", (t) => {
       "doc/Prettier.md",
       "helpers/README.md"
     ],
-    "noInlineConfig": true,
     "config": {
       "line-length": { "line_length": 150 },
       "no-duplicate-heading": false
-    }
+    },
+    "customRules": [ require("markdownlint-rule-github-internal-links") ],
+    "noInlineConfig": true
   };
   markdownlint(options, function callback(err, actual) {
     t.falsy(err);