JMockit Mocks Are Not Being Created

I took the code example from here https://stackoverflow.com/questions/14375854/jmockit-and-fest-ui-testing and put it in a gradle project here https://github.com/opticyclic/assertj-swing-mocks

The [test](https://github.com/opticyclic/assertj-swing-mocks/blob/master/src/test/java/com/github/opticyclic/demo/assertj/SimpleFormTest.java) code inside the `GuiActionRunner` doesn't seem to get mocked even though the code outside it does.

```
@Override
protected void onSetUp() {
//Mock the Service
new Expectations() {{
service.getValue();
result = mockText;
}};

//Demonstrate that the mocking is working here
SimpleService simpleService = new SimpleService();
Assert.assertEquals(simpleService.getValue(), mockText);

JFrame frame = GuiActionRunner.execute(new GuiQuery() {
@Override
protected JFrame executeInEDT() {
SimpleController controller = new SimpleController();

JFrame frame = new JFrame("Simple Frame");
frame.add(controller.getPanel());
frame.setDefaultCloseOperation(WindowConstants.DISPOSE_ON_CLOSE);
frame.pack();
return frame;
}
});
```

The test fails with:
```
java.lang.AssertionError: [javax.swing.JButton[name='testButton', text='Not Mocked', enabled=true, visible=true, showing=true] - property:'text']
Expecting:
"Not Mocked"
to match pattern:
"Mock Button Text"
```

Why are the mocks not being created?