Homebrew with Mac OS 10.15

Solution: 

after upgrading to High Sierra, uninstall brew & re-install with the below command to ensure the linking to the brew github and associated permissions to the local folder work correctly:
/usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"

Reference:
https://gist.github.com/irazasyed/7732946