fix issue nabu 2023.1 with JP2k writer

I have two issues with the JP2K writer.

issue 1

  File "/scisoft/tomotools/x86_64/cuda11/nabu_dev_tomwer_1.0/lib/python3.8/site-packages/nabu/pipeline/utils.py", line 17, in wrapper
    return func(*args, **kwargs)
  File "/scisoft/tomotools/x86_64/cuda11/nabu_dev_tomwer_1.0/lib/python3.8/site-packages/nabu/pipeline/fullfield/chunked.py", line 599, in _init_writer
    self.writer = WriterManager(
  File "/scisoft/tomotools/x86_64/cuda11/nabu_dev_tomwer_1.0/lib/python3.8/site-packages/nabu/pipeline/writer.py", line 153, in __init__
    raise ValueError("Unsupported file format: %s" % file_format)
ValueError: Unsupported file format: jp2

this one should be fixed by the first commit.

issue 2

jp2kvolume.py", line 145, in save_frame
    glymur.Jp2k(file_name, data=frame, psnr=self.psnr, cratios=self.cratios)
  File "/scisoft/tomotools/x86_64/cuda11/nabu_dev_tomwer_1.0/lib/python3.8/site-packages/glymur/jp2k.py", line 249, in __init__
    self._write(data)
  File "/scisoft/tomotools/x86_64/cuda11/nabu_dev_tomwer_1.0/lib/python3.8/site-packages/glymur/jp2k.py", line 900, in _write
    self._populate_cparams(img_array)
  File "/scisoft/tomotools/x86_64/cuda11/nabu_dev_tomwer_1.0/lib/python3.8/site-packages/glymur/jp2k.py", line 874, in _populate_cparams
    self._validate_compression_params(img_array, cparams)
  File "/scisoft/tomotools/x86_64/cuda11/nabu_dev_tomwer_1.0/lib/python3.8/site-packages/glymur/jp2k.py", line 1004, in _validate_compression_params
    self._validate_image_datatype(img_array)
  File "/scisoft/tomotools/x86_64/cuda11/nabu_dev_tomwer_1.0/lib/python3.8/site-packages/glymur/jp2k.py", line 989, in _validate_image_datatype
    raise InvalidJp2kError(msg)
glymur.jp2box.InvalidJp2kError: Only uint8 and uint16 datatypes are currently supported when writing.

I guess there is some cast missing which used to exist before and are no more existing. Or something else