Double attachment of methods to MIAHandler

**Problem:**
This code

```
# Attach methods to Handler explicitly defined in AbstractInputHandler from user_input_handler
for name, _ in inspect.getmembers(AbstractInputHandler, predicate=inspect.isfunction):
if hasattr(user_input_handler, name) and not name.startswith("__"):
attr = getattr(user_input_handler, name)
if callable(attr):
attr = types.MethodType(attr, self) # ensure to properly bind methods to handler
setattr(self, name, attr)
```

is runed both in the MIAHandler.__init__() and the LeakPro.setup_handler(). It's unnecessary to run it twice?

**Solution:**
Can be removed from MIAHandler.__init__() or from LeakPro.setup_handler(). If removed from LeakPro.setup_handler(), the code needs to be added to MINVHandler.__init__().