ValidateInstance. Improve validation message for Enums

[rido-min]

When validating a Enum instance, if the value is not defined in the Enum, the validation message says:

.. does not match any name in schema

I think it should be

.. does not match any value in the Enum

repro:

[TestMethod]
public void ValidateEnumStringInstance ()
{
    const string dtdl = @"
        {
        ""@context"": ""dtmi:dtdl:context;2"",
        ""@id"": ""dtmi:tests:enumString;1"",
        ""@type"": ""Interface"",
        ""displayName"": ""enumString"",
        ""contents"": [
        {
            ""@type"": ""Property"",
            ""name"": ""aPropWithEnum"",
            ""schema"": {
            ""@type"": ""Object"",
            ""fields"": [
                {
                ""name"": ""anEnumString"",
                ""schema"" : {
                    ""@type"": ""Enum"",
                    ""valueSchema"": ""string"",
                    ""enumValues"": [
                    {
                        ""name"": ""optionOne"",
                        ""enumValue"": ""one""
                    },
                    {
                        ""name"": ""optionTwo"",
                        ""enumValue"": ""two""
                    }
                    ]
                }
                }
            ]
            }
        }
        ]
    }
    ";
    var model = new ModelParser().Parse(dtdl)[new Dtmi("dtmi:tests:enumString;1")] as DTInterfaceInfo;
    var anEnumStringSchema = model.Properties["aPropWithEnum"].Schema;
            
    string instanceOk = @"
    {
        ""anEnumString"" : ""two""
    }";
    var validations = anEnumStringSchema.ValidateInstance(instanceOk);
    foreach (var validation in validations) Assert.AreEqual("", validation);
    Assert.AreEqual(0, validations.Count);

    string instanceFails = @"
    {
        ""anEnumString"" : ""four""
    }";
    validations = anEnumStringSchema.ValidateInstance(instanceFails);
    foreach (var validation in validations) Assert.AreEqual("\"anEnumString\" does not match any name in schema", validation);
    Assert.AreEqual(1, validations.Count);
}

[jrdouceur]

@rido-min, this can be closed now, can it not? This bug was fixed by #99 and tested by #101, both of which have been merged into main.

[rido-min]

yes, if we link the PRs to the issues, those will be closed with the PR.