Issue in resampling using Spacingd

[tomDag25]

We faced an issue in the kaggle notebook because the resampling was not working properly. The cause of this malfunction was the presence of the function EnsureChannelFirstd after Spacind and not before.

The function EnsureChannelFirstd should always be called right after LoadImaged.

[abelsalm]

We were really lucky Thomas detected that in the inference code (because wasn't changing our images since it wasn't applied, so it didn't look weird at first sight....)
This should really be something noted somewhere in a guide for next students that would come to use MONAI transforms.