Continuous Fuzz testing - Allow user setup environmental variable during continuous scan creation

Problem

The user might want to add some variable to fine-tune their fuzz testing during the creation. We should allow the user to add the environmental variables as they wish

Solution

Figma:https://www.figma.com/file/iKVb1JXx9fKXdZLbc26l5y/Continous-Fuzzing?node-id=406%3A1507