Add OBSERVE_ROLE_HOLDERS permission to shell.

This allows testing relevant APIs in CTS tests. The listener itself
only gives the changed role name and user affected.

Bug: 125404675
Test: build
Change-Id: I5c979a26dae103ea1b633c2119c59363d8953aa2
diff --git a/packages/Shell/AndroidManifest.xml b/packages/Shell/AndroidManifest.xml
index 0da3b10..fc6ef2b 100644
--- a/packages/Shell/AndroidManifest.xml
+++ b/packages/Shell/AndroidManifest.xml
@@ -146,6 +146,7 @@
     <uses-permission android:name="android.permission.SET_TIME_ZONE" />
     <uses-permission android:name="android.permission.DISABLE_HIDDEN_API_CHECKS" />
     <uses-permission android:name="android.permission.MANAGE_ROLE_HOLDERS" />
+    <uses-permission android:name="android.permission.OBSERVE_ROLE_HOLDERS" />
     <uses-permission android:name="android.permission.STATUS_BAR_SERVICE" />
     <!-- Permission needed to rename bugreport notifications (so they're not shown as Shell) -->
     <uses-permission android:name="android.permission.SUBSTITUTE_NOTIFICATION_APP_NAME" />