* command/format: check for sensitive NestedTypes
Eventually, the diff formatter will need to be updated to properly
handle NestedTypes, but for now we can let the existing function deal
with them as regular cty.Object-type attributes.
To avoid printing sensitive nested attributes, we will treat any
attribute with at least one sensitive nested attribute as an entirely
sensitive attribute.
* bugfix for Object ImpliedType()
ImpliedType() was returning too early when the given object had optional
attributes, therefore skipping the incredibly important step of
accounting for the nesting mode when returning said type.