Replaced [MaybeNullWhen(false)] with [NotNullWhen(true)] for UdiParser.TryParse method (#14880)

* Replaced [MaybeNullWhen(false)] with [NotNullWhen(true)] for UdiParser.TryParse method

* Removing some empty lines

tests/Umbraco.Tests.UnitTests/Umbraco.Core/CoreThings/UdiTests.cs

@@ -205,6 +205,28 @@ public class UdiTests
         Assert.Throws<ArgumentException>(() => new UdiRange(guidUdi, "x"));
     }
 
+    [Test]
+    public void TryParseTest()
+    {
+        // try parse to "Udi"
+        var stringUdiString = "umb://document/b9a56165-6c4e-4e79-8277-620430174ad3";
+        Assert.IsTrue(UdiParser.TryParse(stringUdiString, out Udi udi1));
+        Assert.AreEqual("b9a56165-6c4e-4e79-8277-620430174ad3", udi1 is GuidUdi guidUdi1 ? guidUdi1.Guid.ToString() : string.Empty);
+
+        // try parse to "Udi"
+        Assert.IsFalse(UdiParser.TryParse("nope", out Udi udi2));
+        Assert.IsNull(udi2);
+
+        // try parse to "GuidUdi?"
+        Assert.IsTrue(UdiParser.TryParse(stringUdiString, out GuidUdi? guidUdi3));
+        Assert.AreEqual("b9a56165-6c4e-4e79-8277-620430174ad3", guidUdi3.Guid.ToString());
+
+        // try parse to "GuidUdi?"
+        Assert.IsFalse(UdiParser.TryParse("nope", out GuidUdi? guidUdi4));
+        Assert.IsNull(guidUdi4);
+
+    }
+
     [Test]
     public void SerializationTest()
     {