tests: update network related errors for Debian 9
We have a CI job that runs the Mercurial tests in parallel. Some of the
network related failures seems to be different on the environment. Oddly,
those failures happens only when running the tests in parallel, not when
running the test file only.
I have no idea how to get the windows formatted message for the error, if
someone could give me an hand, I will update this changeset with the value.
Differential Revision: https://phab.mercurial-scm.org/D5401
#
# Avoid interference from actual test env:
unset HGTEST_JOBS
unset HGTEST_TIMEOUT
unset HGTEST_PORT
unset HGTEST_SHELL