tests/test-xdg.t

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

#if no-windows no-osx

  $ mkdir -p xdgconf/hg
  $ echo '[ui]' > xdgconf/hg/hgrc
  $ echo 'username = foobar' >> xdgconf/hg/hgrc
  $ XDG_CONFIG_HOME="`pwd`/xdgconf" ; export XDG_CONFIG_HOME
  $ unset HGRCPATH
  $ hg config ui.username 2>/dev/null
  foobar

#endif