This change extends the functionality for sending emails
in task stages.
Add the following configuration options for configuring
what email address to send task emails to:
* `to` (`str`) - Send the email to the given arbitrary email address
* `email_current_user` (`bool`) - Email the user who initiated the task
New variables have also been added to the task email template context,
to allow referencing other candidate email addresses in the template
(e.g. "A confirmation email has been sent to `<new email address>`
to confirm your email change"):
* `from_address` (`str`) - The email address the email is being sent
from internally. Not always the same as the `From` header,
which is set to `reply_address`.
* `reply_address` (`str`) - The reply-to email address added to the
email header.
* `email_address` (`str`) - The target email address for this
email template.
* `email_current_user_address` (`str | None`) - The email address of
the user that created the task, if available.
* `emails_action_addresses` (`dict[str, str]`) - The recipient
email addresses configured on the task actions, if a recipient
email address is set. The key is the action name, the value is
the target email address.
Multiple emails can now be sent per stage in a task by defining
the `emails` (`list[dict[str, Any]]`) option, and setting
configuration overrides for each individual email.
Change-Id: Ifc83c42bdefcc24e343b8489a917080e6c9785dc
c99499d9df