fix setup.sh test to work with sh only

setup.sh.dist

@@ -1,6 +1,6 @@
 #!/bin/sh
 
-[[ -f .env ]] && echo "JUST DONT" && exit 1
+[ -f .env ] && echo "JUST DONT" && exit 1
 
 ## You can (should) customize those variables
 # the docker-compose project name