Rollup merge of #105560 - GuillaumeGomez:extend-rustdoc-hashtag-prep-line, r=notriddle

Extend rustdoc hashtag prepended line test

Follow-up of https://github.com/rust-lang/rust/pull/105539. This case wasn't checked so better add it.

r? `@notriddle`

src/librustdoc/html/markdown/tests.rs

@@ -343,6 +343,14 @@ fn t(input: &str, expect: &str) {
 #..#.#....#....#....#..#.
 #..#.#....#....#....#..#.
 #..#.####.####.####..##..
+</code></pre></div>",
+    );
+    t(
+        r#"```markdown
+# hello
+```"#,
+        "<div class=\"example-wrap\"><pre class=\"language-markdown\"><code>\
+# hello
 </code></pre></div>",
     );
 }