fix: Add tintColor to Flow FastImageProps type (#871)

Author: MichaelDanielTom

src/index.js.flow

@@ -59,6 +59,7 @@ export type FastImageProps = $ReadOnly<{|
  source?: ?(FastImageSource | number),
  defaultSource?: ?number,
 
+ tintColor?: number | string,
  resizeMode?: ?ResizeModes,
  fallback?: ?boolean,
  testID?: ?string,