fix: jsonUtil ut code check fix (#318)

Author: msslulu

base/src/test/java/com/tinyengine/it/common/utils/JsonUtilsTest.java

@@ -3,6 +3,7 @@
 
 import org.junit.jupiter.api.Test;
 
+import java.nio.charset.StandardCharsets;
 import java.util.List;
 import java.util.Map;
 
@@ -269,7 +270,7 @@ void testEncodePrettily_ComplexObject() {
 	void testDecode_ByteArray() {
 		// Arrange
 		String json = "{\"key\":\"value\",\"number\":123}";
-		byte[] jsonBytes = json.getBytes();
+		byte[] jsonBytes = json.getBytes(StandardCharsets.UTF_8);
 
 		// Act
 		Map<String, Object> result = JsonUtils.decode(jsonBytes, Map.class);