tests/test-gendoc-it.t

tests: skip a detailed exit status in test-lfs-test-server

The mode of failure here differs between `lfs-test-server` and `hg serve`, and
they each throw a different exception.  The `hg serve` case raises a subclass of
`StorageError`, which gets a detailed status.  The `lfs-test-server` case raises
a subclass of `Abort`, which does not.  Since the exit code isn't currently
conditionizable in the tests, this is the simplest way to avoid the failure.

Differential Revision: https://phab.mercurial-scm.org/D9836

#require docutils gettext

  $ $TESTDIR/check-gendoc it
  checking for parse errors