Use single quotes also in $LINE definiton

lib/termsupport.zsh

@@ -27,7 +27,7 @@ function omz_termsupport_preexec {
   emulate -L zsh
   setopt extended_glob
   local CMD=${1[(wr)^(*=*|sudo|ssh|rake|-*)]} #cmd name only, or if this is sudo or ssh, the next cmd
-  local LINE="${2}"
+  local LINE='${2}'
   title "$CMD" '%100>...>$LINE%<<'
 }