Fix outdated custom view example p2

Summary:Forgot to fix the description of the example in #6435

`UIProp` -> `ReactProp`
Closes #6442

Differential Revision: D3056520

fb-gh-sync-id: 0995ba66d550279bb75daa733673c68d37c5c793
shipit-source-id: 0995ba66d550279bb75daa733673c68d37c5c793

Author: janicduplessis

website/src/react-native/index.js

@@ -351,7 +351,7 @@ class Message extends Component {
 
           <h3>Creating Android views</h3>
           <p>
-          Custom Android views can be exposed by extending SimpleViewManager, implementing a createViewInstance and getName methods, and exporting properties with the @UIProp annotation. Then a simple JavaScript file connects the dots.
+          Custom Android views can be exposed by extending SimpleViewManager, implementing a createViewInstance and getName methods, and exporting properties with the @ReactProp annotation. Then a simple JavaScript file connects the dots.
           </p>
           <Prism>
 {`// Java