Set version to 3.2.2-beta

The 3.2.2 release will include quite a few new features which warrant
at least one beta build before RC:

- GLES2 2D batching
- Mono/C# support for iOS
- New Android plugin system

version.py

@@ -3,7 +3,7 @@ name = "Godot Engine"
 major = 3
 minor = 2
 patch = 2
-status = "rc"
+status = "beta"
 module_config = ""
 year = 2020
 website = "https://godotengine.org"