update README to specify that artifacts are not full projects

README.md

@@ -32,7 +32,7 @@ GDExtension template that automatically builds into a self-contained addon for t
 
 ### Distributing your extension on the Godot Asset Library:
 1. Go to Repository→Actions and download the latest artifact.
-2. Test the artifact (it should be a working Godot project).
+2. Test the artifact by extracting the addon into a project.
 3. Create a new release on GitHub, uploading the artifact as an asset.
 4. On the asset, Right Click→Copy Link to get a direct file URL. Don't use the artifacts directly from GitHub Actions, as they expire.
 5. When submitting/updating on the Godot Asset Library, Change "Repository host" to `Custom` and "Download URL" to the one you copied.