Data pattern matching for lists broken between 0.20.2 and 0.21.1

Using httpx==0.25.1

Test case:

```py
def test_respx_data_list():
    with respx.mock:
        respx.post("http://example.com", data={"foo": ["bar"]})
        httpx.post("http://example.com", data={"foo": ["bar"]})
```

In 0.20.2 this test passes as expected. In 0.21.1 it fails with a `AllMockedAssertionError`