feat: add CC and BCC inputs if --cc or --bcc is specified. (#65)

This commit adds CC + BCC hidden inputs and are shown if the user passes
in some value to the `-cc` or `--bcc` flags.

email.go

@@ -156,6 +156,8 @@ func sendResendEmail(to, _, _ []string, from, subject, body string, attachments
 		From:        from,
 		To:          to,
 		Subject:     subject,
+		Cc:          cc,
+		Bcc:         bcc,
 		Html:        html.String(),
 		Text:        body,
 		Attachments: makeAttachments(attachments),