fix(aws): send asr() error message to stderr and reset terminal color (#14027)

asp() already writes its "profile not found" error to stderr and ends
with ${reset_color}; asr() printed its region error to stdout without a
reset, leaving the terminal red and mixing diagnostics into piped output.

Mirror asp() so both selection helpers behave the same.

Refs #13949

plugins/aws/aws.plugin.zsh

@@ -69,7 +69,7 @@ function asr() {
   local -a available_regions
   available_regions=($(aws_regions))
   if [[ -z "${available_regions[(r)$1]}" ]]; then
-    echo "${fg[red]}Available regions: \n$(aws_regions)"
+    echo "${fg[red]}Available regions: \n$(aws_regions)${reset_color}" >&2
     return 1
   fi