fix: MarkdownIt String error when md file body is empty (#303)

* Fix: MarkdownIt String error

Fixed MardownIt String error that occurs when a md file body is empty

* fix dependabot.yml

* fix parsing error

* refactor: simplify content handling in RSS feed generation

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Co-authored-by: アピヌ <apynu@users.noreply.github.com>
Co-authored-by: L4Ph <4ranci0ne@gmail.com>
Co-authored-by: Katsuyuki Karasawa <me@l4ph.moe>

src/pages/rss.xml.ts

@@ -15,12 +15,15 @@ export async function GET(context: APIContext) {
     description: siteConfig.subtitle || 'No description',
     site: context.site ?? 'https://fuwari.vercel.app',
     items: blog.map(post => {
+      const content =
+        typeof post.body === 'string' ? post.body : String(post.body || '')
+
       return {
         title: post.data.title,
         pubDate: post.data.published,
         description: post.data.description || '',
         link: `/posts/${post.slug}/`,
-        content: sanitizeHtml(parser.render(post.body), {
+        content: sanitizeHtml(parser.render(content), {
           allowedTags: sanitizeHtml.defaults.allowedTags.concat(['img']),
         }),
       }