Image: remove unused ImageProps (#28151)

Summary:
I noticed that there was a `height` and `width` props in `Image` component, but those props are not being used in `RCTImageView`(ios) or `ReactImageView`(android).

## Changelog

[GENERAL] [Removed] - Remove Unused ImageProp
Pull Request resolved: https://github.com/facebook/react-native/pull/28151

Test Plan: Start a new React Native Project, and use `Image` component with `width` and `height` props and verify that it does not display the image on both iOS and Android

Reviewed By: shergin

Differential Revision: D20197126

Pulled By: TheSavior

fbshipit-source-id: 186119448826659d7c01c7c8a271157228169c30

Libraries/Image/ImageProps.js

@@ -149,10 +149,6 @@ export type ImageProps = {|
    */
   style?: ?ImageStyleProp,
 
-  // Can be set via props or style, for now
-  height?: ?DimensionValue,
-  width?: ?DimensionValue,
-
   /**
    * Determines how to resize the image when the frame doesn't match the raw
    * image dimensions.