The first parameter of log methods is not a translatable string

Problem/Motivation

Some of the classes implemented by this project use code similar to the following one.

    if ($result['result']) {
      $log_message = $this->t('@type message sent to @email.', [
        '@type' => ucfirst($type),
        '@email' => $to,
      ]);
      $this->logger->notice($log_message);
    }

The first parameter of ::notice() and similar log methods is not a translatable string; it is a literal string.

Proposed resolution

Fix the code that logs a message.