Move packages to env file and allow extras per distro.

Config/ProvisionTests/Dockerfiles/ubuntu

@@ -2,7 +2,7 @@
 
 FROM ubuntu:rolling
 
-RUN apt update && apt dist-upgrade -y && apt install -y git bash curl sudo which
+RUN apt update && apt dist-upgrade -y && apt install -y $PACKAGES $EXTRA_UBUNTU
 
 COPY bin/main.sh /root/main.sh
 RUN chmod +x /root/main.sh