Quoting a list of strings in yaql; for use in bash cmd

list:
["test&","test&","test&"]

in yaql you can get the list in single quotes like so
$.select(concat("'",$,"'")).join(" ")

in st2 that would be something like:
"<%ctx().indicators.FileHashSHA256.select(concat(\"'\",$,\"'\")).join(\"' '\")%>"