Update fail_fast description in configuration.rb
Update fail_fast description in configuration.rb

rspec/rspec-core,xmik/rspec-core,azbshiri/rspec-core,xmik/rspec-core,rspec/rspec-core,azbshiri/rspec-core,Teino1978-Corp/Teino1978-Corp-rspec-core,rspec/rspec-core,xmik/rspec-core,Teino1978-Corp/Teino1978-Corp-rspec-core,Teino1978-Corp/Teino1978-Corp-rspec-core,azbshiri/rspec-core