Fixed typo in contribution guidelines
Fixed typo in contribution guidelines


beautify-web/js-beautify,aecepoglu/js-beautify,Coburn37/js-beautify,bitwiseman/js-beautify,bitwiseman/js-beautify,aecepoglu/js-beautify,beautify-web/js-beautify,mmsqe/js-beautify,Coburn37/js-beautify,mmsqe/js-beautify,Coburn37/js-beautify,bitwiseman/js-beautify,aecepoglu/js-beautify,aecepoglu/js-beautify,beautify-web/js-beautify,Coburn37/js-beautify,beautify-web/js-beautify,mmsqe/js-beautify,bitwiseman/js-beautify,mmsqe/js-beautify