refactor: Fix the newsletter-confirmation process

A few issues in the design of the newsletter confirmation handling process have been addressed:

• The check to ensure that the data inserted into Redis would contain expected parameters was checking for the incorrect keys
• civicrm.repository.report_donation() is no longer used by newsletter-related methods - they aren't reporting donations, after all, and report_donation() now presumes several donation-related things about the data it's handling. civicrm.repository.report_action() has been created to serve instead as a repository-level handler for CiviCRM-bound data unrelated to donations.