CI: Update build and package scripts to require Zsh 5.9

.github/scripts/.build.zsh

@@ -21,8 +21,8 @@ if (( ! ${+CI} )) {
   exit 1
 }
 
-autoload -Uz is-at-least && if ! is-at-least 5.2; then
-  print -u2 -PR "%F{1}${funcstack[1]##*/}:%f Running on Zsh version %B${ZSH_VERSION}%b, but Zsh %B5.2%b is the minimum supported version. Upgrade Zsh to fix this issue."
+autoload -Uz is-at-least && if ! is-at-least 5.9; then
+  print -u2 -PR "%F{1}${funcstack[1]##*/}:%f Running on Zsh version %B${ZSH_VERSION}%b, but Zsh %B5.9%b is the minimum supported version. Upgrade Zsh to fix this issue."
   exit 1
 fi
 

.github/scripts/.package.zsh

@@ -21,8 +21,8 @@ if (( ! ${+CI} )) {
   exit 1
 }
 
-autoload -Uz is-at-least && if ! is-at-least 5.2; then
-  print -u2 -PR "%F{1}${funcstack[1]##*/}:%f Running on Zsh version %B${ZSH_VERSION}%b, but Zsh %B5.2%b is the minimum supported version. Upgrade Zsh to fix this issue."
+autoload -Uz is-at-least && if ! is-at-least 5.9; then
+  print -u2 -PR "%F{1}${funcstack[1]##*/}:%f Running on Zsh version %B${ZSH_VERSION}%b, but Zsh %B5.9%b is the minimum supported version. Upgrade Zsh to fix this issue."
   exit 1
 fi