fix ufbx typo ("ubfx") in available_formats.rst

Author: Lamby777

tutorials/assets_pipeline/importing_3d_scenes/available_formats.rst

@@ -21,7 +21,7 @@ Godot supports the following 3D *scene file formats*:
 - FBX, supported via the `ufbx <https://github.com/ufbx/ufbx>`__ library. The
   previous import workflow used `FBX2glTF <https://github.com/godotengine/FBX2glTF>`__
   integration. This requires installing an external program that links against the
-  proprietary FBX SDK, so we recommend using the default ubfx method or other formats
+  proprietary FBX SDK, so we recommend using the default ufbx method or other formats
   listed above (if suitable for your workflow).
 
 Copy the scene file together with the textures and mesh data (if separate) to