Add settings enum for dnd people page

Test: make
Bug: 137397357
Change-Id: I44915b6dbbdfcb3431bff81add3b403540add2a4
diff --git a/core/proto/android/app/settings_enums.proto b/core/proto/android/app/settings_enums.proto
index b83b31c..cd3887e 100644
--- a/core/proto/android/app/settings_enums.proto
+++ b/core/proto/android/app/settings_enums.proto
@@ -2553,4 +2553,8 @@
     // OS: R
     MANAGE_EXTERNAL_STORAGE = 1822;
 
+    // Open: Settings > DND > People
+    // OS: R
+    DND_PEOPLE = 1823;
+
 }