Remove broken test

src/tests/test_attachment.py

@@ -71,18 +71,3 @@ async def test_rich_data_detection(file_path: pathlib.Path, expected_type, expec
             assert attr in value, f"{key} is not in iterable (expected {value!r}, got {attr!r})"
         else:
             assert attr == value, f"{key} does not match (expected {value!r}, got {attr!r})"
-
-
-@pytest.mark.parametrize(
-    "file_path, expected_value",
-    [
-        (ASSETS / "sample-clouds.webp", "image/webp"),
-        (io.BytesIO((ASSETS / "sample-jpeg.jpg").read_bytes()), "image/png"),
-    ],
-)
-def test_image_converter(file_path: _CT, expected_value: str):
-    _, t = expected_value.split("/")
-    x = io.BytesIO()
-    out = niobot.convert_image(file_path, x, output_format=t)
-    assert niobot.detect_mime_type(out) == expected_value
-    assert niobot.detect_mime_type(x) == expected_value