TkScrolledFrame.configure() doesn't return

[BloodyRain2k]

I've been digging around in the code for something else and out of curiosity, noticed that there's a return missing in
https://github.com/alejandroautalan/pygubu/blob/master/src/pygubu/widgets/tkscrolledframe.py#LL250C9

I've manually created a TkScrolledFrame widget and called .configure() on it and as expected, it didn't return anything.