FindOrCreateContactByEmail action only searches primary email addresses

Overview

FindOrCreateContactByEmail action use

$result = civicrm_api3('Contact', 'getvalue', [
  'return' => "id",
  'email' => $email,
]);

to locate existing contacts. This call only searches primary emails, if a contact has an alternative email address specified, won't be found and a new, duplicate contact will be created.

Proposal

Changing this to

$result = civicrm_api3('Email', 'get', [
  'return' => ["contact_id"],
  'email' => $email,
]);

would find the contact.

Note

I'm happy to provide a PR.