blog: Fix homepage link in rss feed

When following the Node.js Blog at https://nodejs.org/en/blog in a feed reader like NetNewsWire, or when sharing a blog roll via OPML ([example](https://gist.github.com/Krinkle/e0d13f84b91e829afffa7b27822482be)), the homepage link gets broken.

Instead of navigating the browser to the website, one gets a blank page and an unexpected RSS feed download in the background.

The `<link>` tag in RSS 2.0 is for the HTML website. The "self" link for the RSS file itself is already generated by [jpmonette/feed](https://github.com/jpmonette/feed) package.

While at it, also limit the impact of the broken `description` element. This is accepted as parameter here, but not actually passed in `/apps/site/site.json`. The field is optional in RSS, so it's fine to omit. But as-is, it was outputting the string `"undefined"` as the blog's description.


Signed-off-by: Timo Tijhof <krinkle@fastmail.com>

Author: Krinkle

apps/site/next-data/generators/websiteFeeds.mjs

@@ -32,8 +32,8 @@ const generateWebsiteFeeds = ({ posts }) => {
         id: file,
         title: title,
         language: 'en',
-        link: `${canonicalUrl}/feed/${file}`,
-        description: description,
+        link: `${canonicalUrl}/`,
+        description: description || '',
       });
 
       const blogFeedEntries = posts