Not compatible with macOS

Running `find_map_test_cases.py` is producing the following error:

```
OSError: dlopen(/Users/boraelci/methods2test/scripts/java-grammar.so, 0x0006): tried: '/Users/boraelci/methods2test/scripts/java-grammar.so' (not a mach-o file), '/usr/lib/java-grammar.so' (no such file)
```

The `(not a mach-o file)` part indicates an issue with macOS compatibility.