fix bug

hutool-poi/src/test/java/cn/hutool/poi/excel/ExcelWriteTest.java

@@ -727,6 +727,19 @@ public class ExcelWriteTest {
 		writer.close();
 	}
 
+	@Test
+	@Ignore
+	public void mergeForDateTest(){
+		// https://github.com/dromara/hutool/issues/1911
+
+		//通过工具类创建writer
+		String path = "d:/test/mergeForDate.xlsx";
+		FileUtil.del(path);
+		ExcelWriter writer = ExcelUtil.getWriter(path);
+		writer.merge(0, 3, 0, 2, DateUtil.date(), false);
+		writer.close();
+	}
+
 	@Test
 	@Ignore
 	public void changeHeaderStyleTest(){