Reduce visibility of ReactTextInputKeyPressEvent

Summary:
In an attempt to reduce footprint of React Native Android public APIs we are reducing visibility of classes and interfaces that are not meant to be used publicly OR are public but have no usages.
As part of our analysis, which involved looking for usages inside the Meta codebase and code search in OSS, we've detected that this class/interface is public but it's not used from other packages.

If you are using this class or interface please comment in this PR and we will restate the public access.

changelog: [Android][Changed] Reducing visibility of ReactTextInputKeyPressEvent

Reviewed By: RSNara

Differential Revision: D49752135

fbshipit-source-id: d0cabf4161c4fab64f49b10724f82ef0dbaaccd9

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/views/textinput/ReactTextInputKeyPressEvent.java

@@ -14,7 +14,7 @@
 import com.facebook.react.uimanager.events.Event;
 
 /** Event emitted by EditText native view when key pressed */
-public class ReactTextInputKeyPressEvent extends Event<ReactTextInputEvent> {
+class ReactTextInputKeyPressEvent extends Event<ReactTextInputEvent> {
 
   public static final String EVENT_NAME = "topKeyPress";