lib-sieve: store action: Sanitize both specified and virtual mailbox names in log strings.

Before, the virtual mailbox name was not sanitized, which caused control
characters to be displayed in log messages. Also, the mailbox name would be
mentioned twice in the log message, once santized and once unsanitized.

src/lib-sieve/sieve-actions.c

@@ -607,7 +607,7 @@ static void act_store_log_status
 	mailbox_name = str_sanitize(trans->context->mailbox, 128);
 
 	if ( trans->box != NULL ) {
-		const char *mailbox_vname = mailbox_get_vname(trans->box);
+		const char *mailbox_vname = str_sanitize(mailbox_get_vname(trans->box), 128);
 
 		if ( strcmp(mailbox_name, mailbox_vname) != 0 )
 			mailbox_name =