Warnings: Handle missing odie-last-chat-id (#38785)

Committed via a GitHub action: https://github.com/Automattic/jetpack/actions/runs/10304805612

Upstream-Ref: Automattic/jetpack@6eba210

Author: alshakero

composer.lock

@@ -204,7 +204,7 @@ public function get_last_chat_id() {
 
 		$projected_response = array(
 			'odie_chat_id'      => $response->odie_chat_id,
-			'odie_last_chat_id' => $response->odie_last_chat_id,
+			'odie_last_chat_id' => $response->odie_last_chat_id ?? null,
 		);
 
 		return rest_ensure_response( $projected_response );