Build.yaml - mail_recipients erroring on spaces

[jonshern]

if there is a space between two emails sending fails for both emails.
Should be handling stripping the spaces and parsing the list a bit more robustly.

  
mail_recipients: [email protected] // works great
mail_recipients: [email protected], [email protected] // fails sending to both addresses.
mail_recipients: [email protected],[email protected] // works great