Change ASSISTANT_SESSION_UNKNOWN ID

ASSISTANT_SESSION_UNKNOWN is a default value that is not expected to be
used, therefore it does not need to use a reserved value.

Test: Tested locally
BUG: 162956422
FIX: 162956422
Change-Id: Ifa6ae42eb883915d9db3e83566ac71cf02e007f7
diff --git a/packages/SystemUI/src/com/android/systemui/assist/AssistantSessionEvent.kt b/packages/SystemUI/src/com/android/systemui/assist/AssistantSessionEvent.kt
index 8b953fa..be089b1 100644
--- a/packages/SystemUI/src/com/android/systemui/assist/AssistantSessionEvent.kt
+++ b/packages/SystemUI/src/com/android/systemui/assist/AssistantSessionEvent.kt
@@ -21,7 +21,7 @@
 
 enum class AssistantSessionEvent(private val id: Int) : UiEventLogger.UiEventEnum {
     @UiEvent(doc = "Unknown assistant session event")
-    ASSISTANT_SESSION_UNKNOWN(523),
+    ASSISTANT_SESSION_UNKNOWN(0),
 
     @UiEvent(doc = "Assistant session dismissed due to timeout")
     ASSISTANT_SESSION_TIMEOUT_DISMISS(524),