debugcommands: create new debugantivirusrunning command
This writes the EICAR test file to .hg/cache, in an attempt to trigger
an AV scanner's scanning engine. This should let us (in theory) detect
some cases when a user's slowness is a result of AV scanning.
Differential Revision: https://phab.mercurial-scm.org/D8353
#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