Fix ruff/bugbear issue (B015)

B015 Pointless comparison. Did you mean to assign a value?
     Otherwise, prepend `assert` or remove it.

https://docs.astral.sh/ruff/rules/useless-comparison/

Author: DimitriPapadopoulos

zarr/tests/test_storage_v3.py

@@ -286,7 +286,7 @@ def test_rename_nonexisting(self):
 
     def test_get_partial_values(self):
         store = self.create_store()
-        store.supports_efficient_get_partial_values in [True, False]
+        assert store.supports_efficient_get_partial_values in [True, False]
         store[data_root + "foo"] = b"abcdefg"
         store[data_root + "baz"] = b"z"
         assert [b"a"] == store.get_partial_values([(data_root + "foo", (0, 1))])