Bear.py: Correct the maintainers_emails method
Bear.py: Correct the maintainers_emails method

`Bear.maintainers_emails` uses `cls.MAINTAINERS` and
it should use `cls.MAINTAINERS_EMAILS`.

Fixes https://github.com/coala/coala/issues/3566

rimacone/testing2,impmihai/coala,JohnS-01/coala,refeed/coala,coala/coala,Asalle/coala,incorrectusername/coala,meetmangukiya/coala,jayvdb/coala,coala/coala,kartikeys98/coala,SanketDG/coala,yashLadha/coala,RJ722/coala,yashLadha/coala,nemaniarjun/coala,Asnelchristian/coala,damngamerz/coala,MariosPanag/coala,yashtrivedi96/coala,yashLadha/coala,shreyans800755/coala,arush0311/coala,arush0311/coala,shreyans800755/coala,Asalle/coala,Asnelchristian/coala,refeed/coala,MariosPanag/coala,nemaniarjun/coala,netman92/coala,arjunsinghy96/coala,sagark123/coala,NiklasMM/coala,netman92/coala,coala/coala,RJ722/coala,rimacone/testing2,coala-analyzer/coala,meetmangukiya/coala,damngamerz/coala,Nosferatul/coala,kartikeys98/coala,Shade5/coala,JohnS-01/coala,SanketDG/coala,NiklasMM/coala,shreyans800755/coala,Asalle/coala,coala-analyzer/coala,Balaji2198/coala,CruiseDevice/coala,rimacone/testing2,karansingh1559/coala,netman92/coala,aptrishu/coala,Shade5/coala,refeed/coala,MariosPanag/coala,SanketDG/coala,aptrishu/coala,yashtrivedi96/coala,jayvdb/coala,incorrectusername/coala,Nosferatul/coala,Nosferatul/coala,arjunsinghy96/coala,CruiseDevice/coala,arjunsinghy96/coala,kartikeys98/coala,meetmangukiya/coala,ayushin78/coala,Balaji2198/coala,Balaji2198/coala,karansingh1559/coala,Asnelchristian/coala,Shade5/coala,yashtrivedi96/coala,coala-analyzer/coala,ayushin78/coala,CruiseDevice/coala,sagark123/coala,RJ722/coala,impmihai/coala,damngamerz/coala,sagark123/coala,NiklasMM/coala,arush0311/coala,impmihai/coala,jayvdb/coala,nemaniarjun/coala,incorrectusername/coala,JohnS-01/coala,karansingh1559/coala,ayushin78/coala,aptrishu/coala