Add flag to Sessions test app AndroidManifest

Author: tejasd

firebase-sessions/test-app/src/main/AndroidManifest.xml

@@ -43,6 +43,11 @@
       android:process=":second"
       android:theme="@style/Theme.Widget_test_app.NoActionBar" />
 
+    <!--    Update value to 100.0 to always have a fireperf verbose session-->
+    <meta-data
+        android:name="sessions_sampling_percentage"
+        android:value="1.0" />
+
     <meta-data
       android:name="firebase_performance_logcat_enabled"
       android:value="true" />