Support DateOnly / TimeOnly in DynamoDBContext

[Dreamescaper]

Description

Added DateOnly and TimeOnly converters (for both V1 and V2 schemas).

Motivation and Context

Fixes #3673

Testing

Screenshots (if appropriate)

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist

• My code follows the code style of this project
• My change requires a change to the documentation
• I have updated the documentation accordingly
• I have read the README document
• I have added tests to cover my changes
• All new and existing tests passed

License

• I confirm that this pull request can be released under the Apache 2 license

[Dreamescaper]

I have added unit tests which verify added changes.
However, UnitTests project is never executed for net8.0 framework.

I have temporary changed csproj (and commented out lots of non-compiling tests) to make sure that tests are correct.
But at this point they will not be executed automatically.

Not sure if anything could be done in scope of this PR...

[normj]

The changes look good. Can you add a change log file to the PR so I can run it through our internal build system and it will update the change log. To add a change log file add a file a <repo-root>/generator/.DevConfigs/<random-guid>/json with the following content.

{
    "services": [
        {
            "serviceName": "DynamoDBv2",
            "type": "patch",
            "changeLogMessages": [
                "Add Support for DateOnly and TimeOnly in DynamoDB high level libraries. This support is available in .NET 8 and above."
            ]
        }
    ]
}

[Dreamescaper]

Done, thanks for help!

[normj]

Thanks for adding the file. I have submitted the PR through the internal build system.

[normj]

Internal build was successful

[dscpinheiro]

Thanks for the PR, it'll be included in the next V4 preview.

For your test comment, after V4 goes GA I'd like to revisit our test projects to target all frameworks we support, but this is a (much) larger effort that's definitely out of scope for this PR.