Minor issue in JavacFileManager.SortFiles.REVERSE

SonarCloud reports the problem in JavacFileManager.SortFiles.REVERSE definition:
 Neither "Math.abs" nor negation should be used on numbers that could be "MIN_VALUE"

        REVERSE {
            @Override
            public int compare(Path f1, Path f2) {
                return -f1.getFileName().compareTo(f2.getFileName());
            }
        }

Since compareTo can technically return MIN_VALUE, we cannot simply negate it. Luckily, we can just swap the f1 and f2 comparison order to achieve the same effect without exposing us to this corner case.