Update README for new branches

Author: Calinou

README.md

@@ -9,6 +9,10 @@ be used with [Godot Engine](https://godotengine.org), the open source
 - The [`master`](https://github.com/godotengine/godot-demo-projects) branch is compatible with Godot's `master` development branch (next 4.x release).
 - The [`3.x`](https://github.com/godotengine/godot-demo-projects/tree/3.x) branch is compatible with Godot's `3.x` development branch (next 3.x release).
 - The other branches are compatible with the matching stable versions of Godot:
+  - [`4.2`](https://github.com/godotengine/godot-demo-projects/tree/4.2)
+    branch for Godot 4.2.x.
+  - [`4.1`](https://github.com/godotengine/godot-demo-projects/tree/4.1)
+    branch for Godot 4.1.x.
   - [`4.0`](https://github.com/godotengine/godot-demo-projects/tree/4.0)
     branch for Godot 4.0.x.
   - [`3.5`](https://github.com/godotengine/godot-demo-projects/tree/3.5)