packaging: use /usr/bin/python3 shebang for scripts in Debian...
packaging: use /usr/bin/python3 shebang for scripts in Debian
"hg" script is already correct because it is handled by setup.py but
"hg-ssh" will be rewritten by dh_python into "/usr/bin/python" which is
not wanted as we target Python 3. By passing --shebang=/usr/bin/python3
to dh_python3, we force shebangs to be set with this value.
