fix(www): "Features" table „Prefetch linked pages“ copy (#12383)

In the CSV source for this, a `href`s `target` attribute was missing the closing (double)quotes, resulting in some missing copy:

![image](https://user-images.githubusercontent.com/21834/53984598-ef857700-4119-11e9-9518-247512a519f7.png)

This PR fixes this:

![image](https://user-images.githubusercontent.com/21834/53984664-0cba4580-411a-11e9-92c4-d92666279813.png)

docs/features/gatsby-specs.csv

@@ -21,7 +21,7 @@ Performance,Faster content delivery,Static content,3,3,1,2,"Can you build your s
 Gatsby supports this out of the box; adoption is possible with <a href=""https://fossbytes.com/get-jekyll-blog-work-offline/"" target=""_blank"">Jekyll</a> and <a href=""https://wordpress.org/plugins/offline-content/"">WordPress</a>. Squarespace <a href=""https://answers.squarespace.com/questions/56762/i-need-to-run-a-demo-of-my-squarespace-website-offline.html"">doesn't currently support</a> any offline access."
 ,,Prefetch linked pages,3,1,1,0,"<p>Gatsby supports content pre-fetching, out of the box. This means that when a page loads, the content needed to load the next link you click will be loaded in the background while you browse the page.</p>
 
-<p>You can put this together in <a href=""https://stackoverflow.com/questions/9951179/this-is-my-jekyll-with-hash-routing-setup-strategy-is-there-a-better-way"" target=""_blank>Jekyll</a>. The situation is <a href=""https://trevan.co/observations-on-front-end-routing-wordpress/"">considerably more tricky</a> for WordPress & requires maintaining dual PHP and JS templates.</p> "
+<p>You can put this together in <a href=""https://stackoverflow.com/questions/9951179/this-is-my-jekyll-with-hash-routing-setup-strategy-is-there-a-better-way"" target=""_blank"">Jekyll</a>. The situation is <a href=""https://trevan.co/observations-on-front-end-routing-wordpress/"">considerably more tricky</a> for WordPress & requires maintaining dual PHP and JS templates.</p> "
 ,,Page caching,3,3,2,0,"<p>Fingerprinting static resources that aren't expected to change lets browsers serve content locally when a user visits a page they've already been to, as opposed to making an extra network call.</p>
 <p>Gatsby and Jekyll support this out of the box, while WordPress allows this via plugins and Squarespace <a href=""https://answers.squarespace.com/questions/173452/enabling-browser-cache-for-sqaurespace-site.html"">doesn't allow it</a> at all.</p>"
 ,,No extraneous code fetching,3,3,3,3,Extraneous code fetches are typically done by single-page applications written in various JS frameworks; on page load they fetch the code needed to run the entire application rather than just the page that's loaded. Website-building frameworks tend to be fine on this.