Tutorial file for JUnit testing unavailable

### Apache NetBeans version

Apache NetBeans 17

### What happened

I am reading the documentation on how to create JUnit test, and there is a recommended file that we should have open during the walk-through. When I click on the link, it says the file is not available.

### How to reproduce

Click on the JUnit Sol file link in the documentation.

### Did this work correctly in an earlier version?

No / Don't know

### Operating System

Windows

### JDK

JDK11

### Apache NetBeans packaging

Other

### Anything else

_No response_

### Are you willing to submit a pull request?

No

Start with the JUnit testing documentation and inspect the linked “JUnit Sol file” mentioned in the issue. Confirm what the link currently targets, then make the tutorial file available at that location and verify that the link opens it successfully.

Written by the indexing model from the issue text.