Minor change to UNet to permit greater modifiability (#3975)
Minor change to UNet to permit greater modifiability (#3975)

* Minor change to UNet to permit greater modifiability

Signed-off-by: Eric Kerfoot <d831a864163d00632ace88ea9a1b5a3a5ac8adfd@kcl.ac.uk>

* Type fix

Signed-off-by: Eric Kerfoot <d831a864163d00632ace88ea9a1b5a3a5ac8adfd@kcl.ac.uk>

* Reverting minor change

Signed-off-by: Eric Kerfoot <d831a864163d00632ace88ea9a1b5a3a5ac8adfd@kcl.ac.uk>
Project-MONAI/MONAI,Project-MONAI/MONAI,Project-MONAI/MONAI,Project-MONAI/MONAI