Newcomers_Guide.rst: Prohibit deleting forks
Newcomers_Guide.rst: Prohibit deleting forks

Pinned a note alerting not to delete forks.

Closes https://github.com/coala/coala/issues/4387

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