[gtk/ebassi/gidocgen] label: Use markdown for css tree

[Matthias Clasen <matthiasc src gnome org>]

commit 789b248c233164ee9dc41aae46015005238c6453
Author: Matthias Clasen <mclasen redhat com>
Date:   Sat Feb 27 19:47:58 2021 -0500

    label: Use markdown for css tree

 gtk/gtklabel.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/gtk/gtklabel.c b/gtk/gtklabel.c
index 47b584c62c..953d6de07c 100644
--- a/gtk/gtklabel.c
+++ b/gtk/gtklabel.c
@@ -68,13 +68,13 @@
  *
  * # CSS nodes
  *
- * |[<!-- language="plain" -->
+ * ```
  * label
  * ├── [selection]
  * ├── [link]
  * ┊
  * ╰── [link]
- * ]|
+ * ```
  *
  * `GtkLabel` has a single CSS node with the name label. A wide variety
  * of style classes may be applied to labels, such as .title, .subtitle,