Passing Customized rootpathPrefix in Gatling script

I have a gatling gradle set up and want to run my scenario with customized root pathprefix.Does anybody know what would be the correct syntax for that

Currently I run with default prefix like ./gradlew clean build my_simulation

For customized one can I run like this
" ./gradlew clean build my_simulation$GATLING_ROOT_PATH_PREFIX"

or I need to do it differently to pass this parameter.