server: skip logging of ECONNRESET I believe this was exposed by 5492dc20, because the sending of the 500 would have already failed and prevented this logging. On Python 3, this will be a ConnectionResetError, which is a subtype of OSError, which is why we check for both OSError and socket.error. Bonus: this fixes a race in test-hgweb.t where sometimes the ECONNRESET wouldn't happen, because now we just don't log those errors. Differential Revision: https://phab.mercurial-scm.org/D5764