Incorrect return type for ttkMorseSmaleComplex::ReturnSaddleConnectors

[Duncan]

Describe the bug
ttkMorseSmaleComplex::ReturnSaddleConnectors return type is int within:
https://github.com/topology-tool-kit/ttk/blob/dev/core/vtk/ttkMorseSmaleComplex/ttkMorseSmaleComplex.h#L160-L161

but the parameter it is returning is a bool within:
https://github.com/topology-tool-kit/ttk/blob/dev/core/base/morseSmaleComplex/MorseSmaleComplex.h#L413

This will generate a build warning by default in MSVC.

Expected behavior
No build warnings.