Tweak formatting for @pytest.mark.parametrize

This removes the "fmt: off" / "fmt: on" directives around the
`@pytest.mark.parametrize` decoration on test_blob_filter, and
reformats it with black, for consistency with other such
decorations.

The style used there, *if* it could be specified as a rule and thus
used without "fmt:" directives, may be nicer than how black formats
multi-line mark decorations. However, since that decoration was
written, there have been a number of other such decorations, which
have been in black style.

This also removes the only (or only remaining?) "fmt:" directive in
the codebase. As such, it should possibly have been done in gitpython-developers#1760.

test/test_blob_filter.py

@@ -14,14 +14,15 @@
 from git.types import PathLike
 
 
-# fmt: off
-@pytest.mark.parametrize('paths, path, expected_result', [
-    ((Path("foo"),), Path("foo"), True),
-    ((Path("foo"),), Path("foo/bar"), True),
-    ((Path("foo/bar"),), Path("foo"), False),
-    ((Path("foo"), Path("bar")), Path("foo"), True),
-])
-# fmt: on
+@pytest.mark.parametrize(
+    "paths, path, expected_result",
+    [
+        ((Path("foo"),), Path("foo"), True),
+        ((Path("foo"),), Path("foo/bar"), True),
+        ((Path("foo/bar"),), Path("foo"), False),
+        ((Path("foo"), Path("bar")), Path("foo"), True),
+    ],
+)
 def test_blob_filter(paths: Sequence[PathLike], path: PathLike, expected_result: bool) -> None:
     """Test the blob filter."""
     blob_filter = BlobFilter(paths)