Fix Sonar security warnings in Post Types manifest

Set explicit secure defaults for `allowBackup` and `usesCleartextTraffic`
to satisfy static analysis. Main app values override during manifest merge.

Author: oguzkocer

libs/posttypes/src/main/AndroidManifest.xml

@@ -3,8 +3,12 @@
     Activities in this module are declared here and merged into the main app's manifest.
     Using Material3 NoActionBar theme to avoid inheriting the app's action bar.
 -->
-<manifest xmlns:android="http://schemas.android.com/apk/res/android">
-    <application>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools">
+    <application
+        android:allowBackup="false"
+        android:usesCleartextTraffic="false"
+        tools:ignore="UnusedAttribute">
         <activity
             android:name="org.wordpress.android.posttypes.CptPostTypesActivity"
             android:theme="@style/Cpt.NoActionBar"