[devtools] Set dumb value for postgres's db-host to avoid unexpected connection to a local server Currently, if something goes wrong (eg config built before call to startpgcluster) while a pg server is running on localhost, it may connect to this server and run the test in there unexepectedly.

missing-dep-for-interpreter make => make | build-essential | dpkg-dev (usr/*/cubicweb/skeleton/debian/rules.tmpl)