Remove usage of Android API <23 in ReactActivityDelegate

Summary:
Since minSDK was bumped to Android API 23 we are removing support of code using Android API <23 in

chnagelog: [Android][Breaking] Remove support for Android API < 23 in

Differential Revision: D48545501

fbshipit-source-id: bae2b149fa4bf63928d11919070ae420c74b6948

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

@@ -7,12 +7,10 @@
 
 package com.facebook.react;
 
-import android.annotation.TargetApi;
 import android.app.Activity;
 import android.content.Context;
 import android.content.Intent;
 import android.content.res.Configuration;
-import android.os.Build;
 import android.os.Bundle;
 import android.view.KeyEvent;
 import androidx.annotation.Nullable;
@@ -204,7 +202,6 @@ public void onConfigurationChanged(Configuration newConfig) {
     }
   }
 
-  @TargetApi(Build.VERSION_CODES.M)
   public void requestPermissions(
       String[] permissions, int requestCode, PermissionListener listener) {
     mPermissionListener = listener;