The "Save" button should be disabled if keeping the value empty when choosing the third validation data strategy.

[v-Hailishi]

System Information (please complete the following information):
Windows OS: Windows-11-Enterprise-22H2
ML.Net Model Builder 2022: 17.14.4.2317901 (Main Build)
Microsoft Visual Studio Enterprise: 2022(17.5.2)
.Net: 6.0

Describe the bug

• On which step of the process did you run into an issue:
  The "Save" button should be disabled if keeping the value empty when choosing the third validation data strategy.

TestMatrix
https://testpass.blob.core.windows.net/test-pass-data/wikipedia-detox-250-line-data.tsv

To Reproduce
Steps to reproduce the behavior:

1. Select Create a new project from the Visual Studio start window.
2. Choose the C# Console App (.NET Core) project template.
3. Add model builder by right click on the project.
4. Select any scenario.
5. On Data page, choose the data source.
6. Click the "Advanced data options..." link, go to the "Validation data" tab.
7. Choose the third option and keep the value empty.

Expected behavior
The "Save" button should be disabled.

Screenshot

Additional context

[v-Hailishi]

The bug has been fixed on the latest main build 17.14.4.2318101.