Updated the test to reflect the break between class name and qualname

The config uses the public `zarr.buffer.cpu.Buffer`, which differs
from the implementation path `zarr.core.buffer.cpu.Buffer`. This is
OK because the public API for getting the buffer doesn't depend on
where it's implemented at.

Author: TomAugspurger

src/zarr/core/config.py

@@ -64,7 +64,7 @@ def enable_gpu(self) -> ConfigSet:
         Configure Zarr to use GPUs where possible.
         """
         return self.set(
-            {"buffer": "zarr.core.buffer.gpu.Buffer", "ndbuffer": "zarr.core.buffer.gpu.NDBuffer"}
+            {"buffer": "zarr.buffer.gpu.Buffer", "ndbuffer": "zarr.buffer.gpu.NDBuffer"}
         )
 
 

tests/test_config.py

@@ -240,7 +240,7 @@ def test_config_ndbuffer_implementation(store: Store) -> None:
 
 def test_config_buffer_implementation() -> None:
     # has default value
-    assert fully_qualified_name(get_buffer_class()) == config.defaults[0]["buffer"]
+    assert config.defaults[0]["buffer"] == "zarr.buffer.cpu.Buffer"
 
     arr = zeros(shape=(100,), store=StoreExpectingTestBuffer())