ResampleToMatch changes `filename_or_obj` metadata.

[karwojan]

There is a logical mistake in ResampleToMatch(d) transform, because this function copies whole dst metadata (which contains target affine) and put as src metadata into input image. This results in replacing of "filename_or_obj" field in src metadata.

>>> from monai.transforms import LoadImaged, ResampleToMatchd, AddChanneld
>>> data = {"image": "/tmp/image.nii.gz", "labels": "/tmp/labels.mgz"}
>>> data = LoadImaged(["image", "labels"], reader="nibabelreader")(data)
>>> data = AddChanneld(["image", "labels"])(data)
>>> 
>>> print("image filename:", data["image_meta_dict"]["filename_or_obj"])
image filename: /tmp/image.nii.gz
>>> print("labels filename:", data["labels_meta_dict"]["filename_or_obj"])
labels filename: /tmp/labels.mgz
>>> data = ResampleToMatchd("labels", "image_meta_dict")(data)
>>> 
>>> print("image filename:", data["image_meta_dict"]["filename_or_obj"])
image filename: /tmp/image.nii.gz
>>> print("labels filename:", data["labels_meta_dict"]["filename_or_obj"])
labels filename: /tmp/image.nii.gz

filename_or_obj field in labels_meta_dict should stay as it was before ResampleToMatchd transform.

[Nic-Ma]

Hi @karwojan ,

Thanks for your bug report, I will try to fix it ASAP.