gramex.ml.translate fails with pandas > 1.0

[jaidevd]

pip install gramex also installs the latest version of pandas (2.x), which seems to be incompatible with gramex.ml.translate.

Downgrading to pandas<2 fixes this.

Example:

>>> gramex.ml.translate('hola', source='es', target='en', key='...')

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/jaidevd/conda/envs/gtr/lib/python3.11/site-packages/gramex/ml.py", line 395, in translate
    result = result.append(pd.DataFrame(new_data), sort=False)
             ^^^^^^^^^^^^^
  File "/home/jaidevd/conda/envs/gtr/lib/python3.11/site-packages/pandas/core/generic.py", line 5989, in __getattr__
    return object.__getattribute__(self, name)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
AttributeError: 'DataFrame' object has no attribute 'append'. Did you mean: '_append'?