packaging: update the certifi dependency
Not sure if this helps with recent certificate issues[1], but we might as well
keep this modern.
Note that certifi no longer claims py2 support, and there's a PR to add it back
in[2]. Py2 support was dropped in 2020.04.05.2 (which predates what's being
updated here). None of the *.py files have changed since the 2020.6.20 release,
and I was able to call `certifi.where()` in both a virtualenv and with
`hg debugshell` from an MSI install with this version, so we shouldn't be any
worse off than before.
[1] https://foss.heptapod.net/mercurial/tortoisehg/thg/-/issues/5745
[2] https://github.com/certifi/python-certifi/pull/154
Differential Revision: https://phab.mercurial-scm.org/D11609
#require serve
$ hg clone http://localhost:$HGPORT/ copy
abort: * (glob)
[100]
$ test -d copy
[1]
$ "$PYTHON" "$TESTDIR/dumbhttp.py" -p $HGPORT --pid dumb.pid
$ cat dumb.pid >> $DAEMON_PIDS
$ hg clone http://localhost:$HGPORT/foo copy2
abort: HTTP Error 404: * (glob)
[100]
$ killdaemons.py