profile.d/toolbox.sh: set PS1 as explicit string constants

since they are constants there is no need to use printf and embed
binary color codes, which also made it hard to match on toolbox PS1.

Author: juhp

profile.d/toolbox.sh

@@ -48,8 +48,8 @@ fi
 
 if [ -f /run/.containerenv ] \
    && [ -f /run/.toolboxenv ]; then
-    [ "${BASH_VERSION:-}" != "" ] && PS1=$(printf "\[\033[35m\]⬢\[\033[0m\]%s" "[\u@\h \W]\\$ ")
-    [ "${ZSH_VERSION:-}" != "" ] && PS1=$(printf "\033[35m⬢\033[0m%s" "[%n@%m]%~%# ")
+    [ "${BASH_VERSION:-}" != "" ] && PS1='\[\e[35m\]⬢\[\e[0m\][\u@\h \W]\$ '
+    [ "${ZSH_VERSION:-}" != "" ] && PS1=$'\e[35m⬢\e[0m[%n@%m]%~%# '
 
     if ! [ -f "$toolbox_welcome_stub" ]; then
         echo ""