修复单元测试报错

Author: ZhengDaoWang

src/dotnetCampus.OpenXMLUnitConverter/MillisecondTime.cs

@@ -26,8 +26,7 @@ public MillisecondTime(StringValue? millisecond)
                 Milliseconds = value;
                 IsIndefinite = false;
             }
-            else if (Enum.TryParse<IndefiniteTimeDeclarationValues>(millisecond, true, out var result)
-                     && result == IndefiniteTimeDeclarationValues.Indefinite)
+            else if (new IndefiniteTimeDeclarationValues(millisecond) == IndefiniteTimeDeclarationValues.Indefinite)
             {
                 Milliseconds = long.MaxValue;
                 IsIndefinite = true;

tests/dotnetCampus.OpenXmlUnitConverter.Tests/MillisecondTimeTest.cs

@@ -32,7 +32,8 @@ public void ParseMillisecondTimeText()
 
             "传入未定义的 OpenXML 字符串，可以说明未解析".Test(() =>
             {
-                var stringValue = new StringValue(IndefiniteTimeDeclarationValues.Indefinite.ToString());
+                var indefinite = (IEnumValue)IndefiniteTimeDeclarationValues.Indefinite;
+                var stringValue = new StringValue(indefinite.Value);
                 var millisecondTime = new MillisecondTime(stringValue);
                 Assert.AreEqual(true, millisecondTime.IsIndefinite);
             });