Cannot invoke "org.netbeans.modules.gsf.testrunner.api.Testcase.getTrouble()" because "testcase" is null

### Apache NetBeans version

Apache NetBeans 25

### What happened

When running a unit test on a freeform project the subject line error occurs. Out put from IDE.log:

```
java.lang.NullPointerException: Cannot invoke "org.netbeans.modules.gsf.testrunner.api.Testcase.getTrouble()" because "testcase" is null
at org.netbeans.modules.junit.ant.JUnitOutputReader.addStackTraceLine(JUnitOutputReader.java:949)
at org.netbeans.modules.junit.ant.JUnitOutputReader.messageLogged(JUnitOutputReader.java:335)
at org.netbeans.modules.junit.ant.JUnitAntLogger.messageLogged(JUnitAntLogger.java:105)
[catch] at org.apache.tools.ant.module.bridge.impl.NbBuildLogger.messageLogged(NbBuildLogger.java:597)
at org.apache.tools.ant.Project.fireMessageLoggedEvent(Project.java:2265)
at org.apache.tools.ant.Project.fireMessageLogged(Project.java:2364)
at org.apache.tools.ant.Project.log(Project.java:481)
at org.apache.tools.ant.Task.log(Task.java:294)
at org.apache.tools.ant.taskdefs.LogOutputStream.processLine(LogOutputStream.java:100)
at org.apache.tools.ant.taskdefs.optional.junit.JUnitTask$JUnitLogOutputStream.processLine(JUnitTask.java:2277)
at org.apache.tools.ant.taskdefs.LogOutputStream.processLine(LogOutputStream.java:90)
at org.apache.tools.ant.util.LineOrientedOutputStream.processLine(LineOrientedOutputStream.java:109)
at org.apache.tools.ant.util.LineOrientedOutputStream.processBuffer(LineOrientedOutputStream.java:81)
at org.apache.tools.ant.taskdefs.LogOutputStream.processBuffer(LogOutputStream.java:77)
at org.apache.tools.ant.util.LineOrientedOutputStream.write(LineOrientedOutputStream.java:58)
at org.apache.tools.ant.util.LineOrientedOutputStream.write(LineOrientedOutputStream.java:150)
at org.apache.tools.ant.taskdefs.StreamPumper.run(StreamPumper.java:141)
at java.base/java.lang.Thread.run(Thread.java:1575)
```

[messages.log](https://github.com/user-attachments/files/19854988/messages.log)

### Language / Project Type / NetBeans Component

Java Free-Form Project

### How to reproduce

Not quite sure, but simply running a unit test w/ (Unit 4.13.2) and (Hamcrest 1.3)

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

No / Don't know

### Operating System

macOS Sequoia: 15.3.2 (24D81)

### JDK

openjdk version "23.0.2" 2025-01-21 OpenJDK Runtime Environment (build 23.0.2+7-58) OpenJDK 64-Bit Server VM (build 23.0.2+7-58, mixed mode, sharing)

### Apache NetBeans packaging

Apache NetBeans provided installer

### Anything else

I have noticed this in the past few NetBeans releases, 24, 23, etc. Not sure how far back I remember.

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

No

Start with org.netbeans.modules.junit.ant.JUnitOutputReader.java at line 949 and reproduce by running a unit test in a Java free-form project with JUnit 4.13.2 and Hamcrest 1.3. Trace the logged output that reaches addStackTraceLine; done means the test run no longer raises a NullPointerException when testcase is null.

Written by the indexing model from the issue text.