Apply suggestions from code review

Co-authored-by: Yan <61414485+yanthomasdev@users.noreply.github.com>

Author: florian-lefebvre

src/content/docs/en/guides/upgrade-to/v6.mdx

@@ -592,9 +592,9 @@ If you need more control over environment variables in Astro, we recommend you u
 
 In Astro 5.5, the `experimental.headingIdCompat` flag was introduced to make the IDs generated by Astro for Markdown headings compatible with common platforms like GitHub and npm, using the popular [`github-slugger`](https://github.com/Flet/github-slugger) package.
 
-In Astro 5.x, Astro had an additional default processing step that stripped a trailing hyphen from the end of IDs for headings ending in special characters.
+In Astro 5.x, Astro had an additional default processing step that stripped trailing hyphens from the end of IDs for headings ending in special characters.
 
-Astro 6.0 removes this experimental flag and makes this the new default behavior in Astro: trailing hyphen from the end of IDs for headings ending in special characters isn't stripped anymore.
+Astro 6.0 removes this experimental flag and makes this the new default behavior in Astro: trailing hyphens from the end of IDs for headings ending in special characters aren't stripped anymore.
 
 #### What should I do?
 
@@ -676,7 +676,7 @@ will generate the following HTML:
        visit(tree, 'element', (node) => {
          if (headingRank(node) && !node.properties.id) {
            let slug = slugs.slug(toString(node));
-           // Strip trailing hyphen like in Astro v5 and below:
+           // Strip trailing hyphens like in Astro v5 and below:
            if (slug.endsWith('-')) slug = slug.slice(0, -1);
            node.properties.id = slug;
          }