Codegen compilation error with 2021-06 M3

[odockal]

[ERROR] Failed to execute goal org.eclipse.tycho:tycho-compiler-plugin:2.2.0:compile (default-compile) on project org.eclipse.reddeer.codegen: Compilation failure: Compilation failure: 
[ERROR] /home/odockal/git/reddeer/plugins/org.eclipse.reddeer.codegen/src/org/eclipse/reddeer/codegen/wizards/MethodsPage.java:[102] 
[ERROR] 	fMethodOptionStubsButtons = new MethodStubsSelectionButtonGroup(SWT.CHECK, optionalButtonNames, 1) {
[ERROR] 			@Override
[ERROR] 			protected void doWidgetSelected(SelectionEvent e) {
[ERROR] 				super.doWidgetSelected(e);
[ERROR] 				// saveWidgetValues();
[ERROR] 				handleSelectedOptional(e);
[ERROR] 			}
[ERROR] 		};
[ERROR] 	                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[ERROR] The constructor MethodStubsSelectionButtonGroup(int, String[], int) is undefined

[odockal]

bugzilla introducing breaking changes here and gerrit commits: 1, 2. Because of quite late finding of breaking changes to reddeer codegen (RC1 + 3) there are limited options as of fixes now.

[odockal]

And of course some UI changes in Test config dialog.