Mailpit 1.21.7

Chore

• Display "To" details in mobile messages list
• Display "From" details in message sidebar (desktop) (#403)
• Stricter SMTP 'MAIL FROM' & 'RCPT TO' handling (#409)
• Move smtpd & pop3 modules to internal
• Bump Go version for automated testing
• Update Go dependencies
• Update node dependencies

Fix

• Prevent splitting multi-byte characters in message snippets (#404)
• Ignore unsupported optional SMTP 'MAIL FROM' parameters (#407)

Testing

• Add smtpd tests