Fix bashism in docker-setup (#476)

Co-authored-by: nnyyxxxx <nnyyxxxx@users.noreply.github.com>

Author: Nyx

tabs/system-setup/6-docker-setup.sh

@@ -9,7 +9,8 @@ choose_installation() {
     printf "%b\n" "1. ${YELLOW}Docker${RC}"
     printf "%b\n" "2. ${YELLOW}Docker Compose${RC}"
     printf "%b\n" "3. ${YELLOW}Both${RC}"
-    read -p "Enter your choice [1-3]: " CHOICE
+    printf "Enter your choice [1-3]: "
+    read -r CHOICE
 
     case "$CHOICE" in
         1) INSTALL_DOCKER=1; INSTALL_COMPOSE=0 ;;