Update deprecation message for ReactNativeHost class (#53118)

Summary:
Pull Request resolved: #53118

Update deprecation message for ReactNativeHost class

changelog: [internal] internal

Reviewed By: shwanton

Differential Revision: D79677829

fbshipit-source-id: 5013e0988a1ffbfea49a261fd23ac71af76c3313

Author: mdvacca

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/ReactNativeHost.java

@@ -35,7 +35,8 @@
  *
  * @deprecated This class will be replaced by com.facebook.react.ReactHost in the New Architecture.
  */
-@Deprecated
+@Deprecated(
+    since = "This class is part of Legacy Architecture and will be removed in a future release")
 @LegacyArchitecture(logLevel = LegacyArchitectureLogLevel.ERROR)
 @Nullsafe(Nullsafe.Mode.LOCAL)
 public abstract class ReactNativeHost {