Describe the issue:

19ba7c4 (#22707) broke string comparison between unyt.unyt_quantity object (fancy 0d numpy arrays with unit data), and strings.

The following minimal example used to be fine, but it crashes on the main branch of numpy

Reproduce the code example:

import unyt as un

a = 1 * un.cm
assert a != "hello"

Error message:

-traceback
Traceback (most recent call last):
  File "/Users/robcleme/dev/numpy/t.py", line 4, in <module>
    assert a != "hello"
           ^^^^^^^^^^^^
  File "/Users/robcleme/.pyenv/versions/numpy-dev/lib/python3.11/site-packages/unyt/array.py", line 1850, in __array_ufunc__
    new_dtype = np.dtype("f" + str(inp1.dtype.itemsize))
                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
TypeError: data type 'f20' not understood

NumPy/Python version information:

Python 3.11.0

Context for the issue:

This change of behaviour breaks yt, see yt-project/yt#4241
I note that we haven't captured this regression via unyt's on CI, so I'll add a test there. (edit: this is yt-project/unyt#333)

It is unclear to me why this is happening, and I am not sure which of numpy or unyt this bug should be fixed in.

Ping @ngoldbaum for information