(CI) update styling

Author: MatthijsBurgh

.ci/pre_deploy.bash

@@ -10,9 +10,9 @@ do
     case $i in
         * )
             # unknown option
-            if [[ -n "$i" ]]
+            if [[ -n "${i}" ]]
             then
-                echo -e "\e[35m\e[1mUnknown input argument '$i'. Check CI yaml file\e[0m"
+                echo -e "\e[35m\e[1mUnknown input argument '${i}'. Check CI yaml file\e[0m"
                 exit 1
             fi ;;
     esac