test: add code-linking test

Author: mcanouil

tests/docs/smoke-all/2025/08/14/issue13216.qmd

@@ -0,0 +1,24 @@
+---
+title: "Issue 13216"
+format: html
+code-annotations: below
+code-link: true
+_quarto:
+  tests:
+    html:
+      ensureHtmlElements:
+        -
+          - "dl.code-annotation-container-grid"
+---
+
+`downlit` (`code-link`) should be disable and `code-annotations` should be enabled.
+
+```
+hello
+```
+
+```{r}
+2 + 2 # <1>
+```
+
+1. This should be styled as a popup.