[gtk/ebassi/gidocgen: 339/501] windowcontrols: Use markdown for css tree

[Emmanuele Bassi <ebassi src gnome org>]

commit 3a32bac5104c7308c284b644786e1663f1f06b65
Author: Matthias Clasen <mclasen redhat com>
Date:   Sat Feb 27 20:08:09 2021 -0500

    windowcontrols: Use markdown for css tree

 gtk/gtkwindowcontrols.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/gtk/gtkwindowcontrols.c b/gtk/gtkwindowcontrols.c
index c364939689..5cd8bce1c9 100644
--- a/gtk/gtkwindowcontrols.c
+++ b/gtk/gtkwindowcontrols.c
@@ -64,13 +64,13 @@
  *
  * # CSS nodes
  *
- * |[<!-- language="plain" -->
+ * ```
  * windowcontrols
  * ├── [image.icon]
  * ├── [button.minimize]
  * ├── [button.maximize]
  * ╰── [button.close]
- * ]|
+ * ```
  *
  * A `GtkWindowControls`' CSS node is called windowcontrols. It contains
  * subnodes corresponding to each title button. Which of the title buttons