New: Add “less” syntax highlighting in Markdown files (#1520)

Author: zhzz

src/loaders/utils/__tests__/highlightCode.spec.ts

@@ -17,7 +17,7 @@ it('should warn when language not found', () => {
 	const actual = highlightCode(code, 'pizza');
 	expect(actual).toBe(code);
 	expect(warn).toBeCalledWith(
-		'Syntax highlighting for “pizza” isn’t supported. Supported languages are: markup, xml, html, mathml, svg, css, clike, javascript, js, markdown, md, scss, flow, typescript, ts, jsx, tsx, graphql, json, bash, shell, diff.'
+		'Syntax highlighting for “pizza” isn’t supported. Supported languages are: markup, xml, html, mathml, svg, css, clike, javascript, js, markdown, md, scss, less, flow, typescript, ts, jsx, tsx, graphql, json, bash, shell, diff.'
 	);
 });
 

src/loaders/utils/highlightCode.ts

@@ -7,6 +7,7 @@ import 'prismjs/components/prism-markdown';
 import 'prismjs/components/prism-css';
 import 'prismjs/components/prism-css-extras';
 import 'prismjs/components/prism-scss';
+import 'prismjs/components/prism-less';
 import 'prismjs/components/prism-javascript';
 import 'prismjs/components/prism-flow';
 import 'prismjs/components/prism-typescript';