Wrap HTMl in markdown code

lighthouse-core/audits/uses-rel-preload.js

@@ -18,10 +18,10 @@ const UIStrings = {
   /** Imperative title of a Lighthouse audit that tells the user to use <link rel=preload> to initiate important network requests earlier during page load. This is displayed in a list of audit titles that Lighthouse generates. */
   title: 'Preload key requests',
   /** Description of a Lighthouse audit that tells the user *why* they should preload important network requests. The associated network requests are started halfway through pageload (or later) but should be started at the beginning. This is displayed after a user expands the section to see more. No character length limits. '<link rel=preload>' is the html code the user would include in their page and shouldn't be translated. 'Learn More' becomes link text to additional documentation. */
-  description: 'Consider using <link rel=preload> to prioritize fetching resources that are ' +
+  description: 'Consider using `<link rel=preload>` to prioritize fetching resources that are ' +
     'currently requested later in page load. [Learn more](https://developers.google.com/web/tools/lighthouse/audits/preload).',
   /** A warning message that is shown when the user tried to follow the advice of the audit, but it's not working as expected. Forgetting to set the `crossorigin` HTML attribute, or setting it to an incorrect value, on the link is a common mistake when adding preload links. */
-  crossoriginWarning: 'A preload <link> was found for "{preloadURL}" but was not used ' +
+  crossoriginWarning: 'A preload `<link>` was found for "{preloadURL}" but was not used ' +
     'by the browser. Check that you are using the `crossorigin` attribute properly.',
 };