Update notification icon.

app/src/main/res/drawable-anydpi-v24/ongoing_notification_icon.xml

+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp"
+    android:height="24dp"
+    android:viewportWidth="26.086956"
+    android:viewportHeight="26.086956"
+    android:tint="#FFFFFF">
+  <group android:translateX="1.0434783"
+      android:translateY="1.0434783">
+    <path
+        android:fillColor="#FF000000"
+        android:pathData="M7.88,3.39L6.6,1.86 2,5.71l1.29,1.53 4.59,-3.85zM22,5.72l-4.6,-3.86 -1.29,1.53 4.6,3.86L22,5.72zM12,4c-4.97,0 -9,4.03 -9,9s4.02,9 9,9c4.97,0 9,-4.03 9,-9s-4.03,-9 -9,-9zM12,20c-3.87,0 -7,-3.13 -7,-7s3.13,-7 7,-7 7,3.13 7,7 -3.13,7 -7,7zM9,11h3.63L9,15.2L9,17h6v-2h-3.63L15,10.8L15,9L9,9v2z"/>
+  </group>
+</vector>