ConfigurationGathering.py: Update docstring
ConfigurationGathering.py: Update docstring

Added the :return: statement documentation at line # 152.

Closes https://github.com/coala/coala/issues/4534

damngamerz/coala,damngamerz/coala,Nosferatul/coala,kartikeys98/coala,coala/coala,SanketDG/coala,coala/coala,rimacone/testing2,Nosferatul/coala,CruiseDevice/coala,Asalle/coala,aptrishu/coala,jayvdb/coala,karansingh1559/coala,kartikeys98/coala,nemaniarjun/coala,aptrishu/coala,coala-analyzer/coala,aptrishu/coala,nemaniarjun/coala,coala-analyzer/coala,shreyans800755/coala,nemaniarjun/coala,rimacone/testing2,SanketDG/coala,karansingh1559/coala,shreyans800755/coala,Asalle/coala,CruiseDevice/coala,damngamerz/coala,Asalle/coala,shreyans800755/coala,Nosferatul/coala,coala/coala,coala-analyzer/coala,jayvdb/coala,jayvdb/coala,rimacone/testing2,karansingh1559/coala,CruiseDevice/coala,SanketDG/coala,kartikeys98/coala