[Swift] Remove ObjC formatter hooks for Set & Dictionary
[Swift] Remove ObjC formatter hooks for Set & Dictionary

AFAICT they are unnecessary -- simply registering Swift formatters for the ObjC class names of storage/bridging classes works just as well.

apple/swift-lldb,apple/swift-lldb,apple/swift-lldb,apple/swift-lldb,apple/swift-lldb,apple/swift-lldb