Recommend official Blender downloads in Importing 3D scenes

This avoids many issues found on Linux when using Blender to import
3D scenes in Godot.

Blender developers themselves only support official downloads,
not Linux distribution packages or the Flatpak.

tutorials/assets_pipeline/importing_scenes.rst

@@ -111,6 +111,11 @@ Importing ``.blend`` files directly within Godot
     recommend using Blender 3.5 or later, as it includes many fixes to the glTF
     exporter.
 
+    It is **strongly** recommended to use an official Blender release downloaded
+    from blender.org, as opposed to a Linux distribution package or Flatpak.
+    This avoids any issues related to packaging, such as different library
+    versions that can cause incompatibilities or sandboxing restrictions.
+
 From Godot 4.0 onwards, the editor can directly import ``.blend`` files by
 calling `Blender <https://www.blender.org/>`__'s glTF export functionality in a
 transparent manner.