Remove parent activity from TTS_SETTINGS

So back button takes user back within their original nav stack.

Fixes: 131395471
Test: manual
Change-Id: I144f4122dca2db6c416412737f9aa07507c5a45f
diff --git a/AndroidManifest.xml b/AndroidManifest.xml
index 5149b9c..39e20dd 100644
--- a/AndroidManifest.xml
+++ b/AndroidManifest.xml
@@ -1462,8 +1462,7 @@
 
         <activity
             android:name="Settings$TextToSpeechSettingsActivity"
-            android:label="@string/tts_settings"
-            android:parentActivityName="Settings">
+            android:label="@string/tts_settings">
             <intent-filter android:priority="1">
                 <action android:name="com.android.settings.TTS_SETTINGS" />
                 <category android:name="android.intent.category.DEFAULT" />