DataAnalyzer in auto3dseg will record negative numbers of spacing

[XIANYUNYEHE-DEL]

Describe the bug
I use DataAnalyzer to statistic LITS dataset, but i get some negative numbers of spacings in data_stats.yaml.

spacing: - [-0.9765620231628418, 0.9765620231628418, 2.5]

I check this file in 3D Slicer, and get IJK to RAS Direction Matrix [-1.0000, 1.0000, 1.0000]. It seems that this is the reason for the negative spacing. I check other negative spacing data and find the same phenomenon. It will cause problems in the stats_summary and create the wrong information of spacing.

[wyli]

agreed, this is probably incorrect:

MONAI/monai/auto3dseg/analyzer.py

Lines 245 to 247 in 731c743

	report[ImageStatsKeys.SPACING] = np.tile(
	np.diag(data[self.image_meta_key]["affine"])[:3], [len(ndas), 1]
	).tolist()

it should be done with metatensor.pixdim or

MONAI/monai/data/utils.py

Line 688 in 731c743

def affine_to_spacing(affine: NdarrayTensor, r: int = 3, dtype=float, suppress_zeros: bool = True) -> NdarrayTensor:

[mingxin-zheng]

A related issue here: #5201

@XIANYUNYEHE-DEL what needed to change seems straightforward to me. I will submit a PR to fix this.
@wyli Can the PR remove the meta_key_postfix completely or we need a few versions to deprecate it?

[mingxin-zheng]

@XIANYUNYEHE-DEL I created a PR to fix this. Thanks for bringing it to our attention!