doc, tools: add doc linting to CI

PR-URL: https://github.com/nodejs/node/pull/12640
Fixes: https://github.com/nodejs/node/issues/12635
Refs: https://github.com/nodejs/node/pull/12563
Reviewed-By: Teddy Katz <teddy.katz@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Michael Dawson <michael_dawson@ca.ibm.com>
Reviewed-By: Gibson Fahnestock <gibfahn@gmail.com>

Makefile

@@ -861,7 +861,7 @@ jslint:
 jslint-ci:
 	@echo "Running JS linter..."
 	$(NODE) tools/jslint.js $(PARALLEL_ARGS) -f tap -o test-eslint.tap \
-		benchmark lib test tools
+		benchmark doc lib test tools
 
 CPPLINT_EXCLUDE ?=
 CPPLINT_EXCLUDE += src/node_root_certs.h

tools/jslint.js

@@ -1,6 +1,7 @@
 'use strict';
 
 const rulesDirs = ['tools/eslint-rules'];
+const extensions = ['.js', '.md'];
 // This is the maximum number of files to be linted per worker at any given time
 const maxWorkload = 40;
 
@@ -14,7 +15,8 @@ const glob = require('./eslint/node_modules/glob');
 
 const cwd = process.cwd();
 const cliOptions = {
-  rulePaths: rulesDirs
+  rulePaths: rulesDirs,
+  extensions: extensions,
 };
 
 // Check if we should fix errors that are fixable

vcbuild.bat

@@ -428,7 +428,7 @@ goto exit
 
 :jslint-ci
 echo running jslint-ci
-%config%\node tools\jslint.js -J -f tap -o test-eslint.tap benchmark lib test tools
+%config%\node tools\jslint.js -J -f tap -o test-eslint.tap benchmark doc lib test tools
 goto exit
 
 :no-lint