ButtonProps iconRight: ButtonIcon, not boolean

Details:
*Type of iconRight in ButtonProps should be a ButtonIcon, not boolean.
*Button is expecting iconRight prop to be a ButtonIcon and will render it appropriately.
*Currently, setting iconRight to a boolean causes error "In this environment the sources for assign MUST be an object."

types/react-native-elements/index.d.ts

@@ -255,11 +255,9 @@ export interface ButtonProps extends TouchableWithoutFeedbackProps {
     fontWeight?: string;
 
     /**
-     * Moves icon to right of title
-     *
-     * @default false
+     * Icon configuration
      */
-    iconRight?: boolean;
+    iconRight?: ButtonIcon;
 
     /**
      * onPress method