Summary:
Remove the older implementation of image instrumentation in Fabric by removing, RCTImageInstrumentationProxy, ImageInstrumentation from ImageRequest, and trackURLImageContentDidSetForRequest from RCTImageLoaderWithAttributionProtocol.
Changelog: [RN][Fabric][Image] Remove unused Fabric image instrumentation
Reviewed By: fkgozali
Differential Revision: D23990606
fbshipit-source-id: 004d04025d031af11377a73e5bfb64b1e0449962