fixing typo

src/message_api.c

@@ -1257,7 +1257,7 @@ static message* wrap_message_as_attachment(message* envelope,
         else {
             _envelope->longmsg = strdup(
                 "This message was encrypted with p≡p (https://pep.software). If you are seeing this message,\n" 
-                "your client does not support raising message attachments. Please click on the message attachment to\n"
+                "your client does not support raising message attachments. Please click on the message attachment\n"
                 "to view it, or better yet, consider using p≡p!\n"
             );
         }