fix: update back-to-top button DOM placement

Resolves #614

Author: satnaing

src/pages/posts/[...slug]/index.astro

@@ -146,12 +146,12 @@ const ogImage = ogImageUrl
 
     <EditPost class="sm:hidden" {hideEditPost} {post} />
 
+    <BackToTopButton />
+
     <ul class="mt-4 mb-8 flex flex-wrap gap-4 sm:my-8">
       {tags.map(tag => <Tag tag={slugifyStr(tag)} tagName={tag} size="sm" />)}
     </ul>
 
-    <BackToTopButton />
-
     <ShareLinks />
 
     <hr class="my-8 border-dashed" />