Validation error when trying to update an image block

[Lysandros-SLR]

When sending a BlockUpdateRequest with an Image a 400 is returned with a validation error. A type should not be passed in when updating an image it would seem. I tried putting in nothing for the type and got the following error

"body failed validation: body.image.type should be not present, instead was ""."

Tested manually and was able to update the block by not passing in a type.

[Chirab]

I think we need to add "omitempty" tag within Type
I also have this problem when updating pdf