Remove abandoned IMAP libraries (#1403)

Remove Fetch and PHP IMAP as both projects appear to be abandoned.

See: https://github.com/ziadoz/awesome-php/pull/1210#pullrequestreview-4004243930

README.md

 * [ddeboer/imap](https://github.com/ddeboer/imap) - Object-oriented, fully tested PHP IMAP library.
 * [Email Reply Parser](https://github.com/willdurand/EmailReplyParser) - An email reply parser library.
 * [Email Validator](https://github.com/nojacko/email-validator) - A small email address validation library.
-* [Fetch](https://github.com/tedious/Fetch) - An IMAP library.
 * [Mautic](https://github.com/mautic/mautic) - Email marketing automation
 * [PHPMailer](https://github.com/PHPMailer/PHPMailer) - Another mailer solution.
-* [PHP IMAP](https://github.com/barbushin/php-imap) - A library to access mailboxes via POP3, IMAP and NNTP.
 * [Stampie](https://github.com/Stampie/Stampie) - A library for email services such as [SendGrid](https://sendgrid.com/en-us), [PostMark](https://postmarkapp.com), [MailGun](https://www.mailgun.com/) and [MailChimp](https://mailchimp.com/features/transactional-email/).
 * [SwiftMailer](https://swiftmailer.symfony.com/docs/introduction.html) - A mailer solution.
 * [Symfony Mailer](https://github.com/symfony/mailer) - A powerful library for creating and sending emails.