Fixed infinite loop on the dashboards

src/utils/users.be.ts

@@ -86,6 +86,9 @@ export async function getLinkedUsers(userID?: string, userType?: Type, type?: Ty
 		...(userType === "teacher" ? belongingGroups.flatMap((x) => x.participants) : []),
 	]);
 
+	//  ⨯ [FirebaseError: Invalid Query. A non-empty array is required for 'in' filters.] {
+	if(participants.length === 0) return {users: [], total: 0};
+
 	const snapshot = await getDocs(query(collection(db, "users"), ...[where(documentId(), "in", participants), ...q]));
 	const users = snapshot.docs.map((doc) => ({
 		id: doc.id,