WP Mail SMTP Pro 4.2.0

### Added:
- New transactional mailer: Mailjet integration.
- Discord integration for the Alerts feature.
- New Zoho region: Canada.

### Changed:
- Improved security for sensitive data (API keys).
- Improved performance of Email Logs and Email Reports queries.

### Fixed:
- Fatal error on the Alerts screen when alert title translation are missing.
- SMTP2GO mailer special characters handling in from name.
- Incomplete CSV and XLSX email log export.

### Changed:
- Delete `wp-mail-smtp` uploads folder on plugin uninstall, if the "Misc > Uninstall" option is enabled.
- Decreased `PHPMailer` timeout value to 30 seconds from 5 minutes.
- Improved Weekly Summary Email sending.




### Fixed:
- Missing Reply-To support in SMTP2GO mailer.
- Setup Wizard translations not working correctly.

### Added:
- New transactional mailer: SMTP2GO.
- Microsoft Teams integration for the Alerts feature.

### Changed:
- Recurring email queue tasks are now removed after completion.

### Fixed:
- Gmail mailer compatibility with network-wide settings on multisite setups.
- Wrong namespace in PHP 8.0x Symfony polyfills.
- All pending background tasks are now canceled on plugin deactivation.
- PHP warnings in Lite translations update checks.
- Slack alerts not working on sites with long titles.
- License key validation issues after license changes.
- Click Link Tracking PHP warning with malformed HTML emails.
- Long email headers incorrectly truncated.