argsort: default value of stable not tested

[cakedev0]

See issue: data-apis/array-api-compat#354

This section of the test:

    kw = data.draw(
        hh.kwargs(
            axis=st.integers(-x.ndim, x.ndim - 1),
            descending=st.booleans(),
            stable=st.booleans(),
        ),
        label="kw",
    )

Probably enforces there are always kwargs, so we don't test default values to behave as expected...

[cakedev0]

I would have been happy to write the PR, but the heavy use of hypothesis makes it hard for me, I don't know this lib.