[pkg] Run test suite as part of autopkgtest Add support for autopkgtest. The test “unittest” will run the test suite using pytest. As we need PostgreSQL in the test environment and open network connection, the test is marked with `isolation-container` and requires at least LXC to be run, e.g: autopkgtest -s -- lxc -s autopkgtest-sid

Tests: unittest
Depends:
 python3-cubicweb,
 @builddeps@,
 python3-pytest,
 python3-crypto, python3-psycopg2,
 postgresql, postgresql-plpython,
 firefox
Restrictions: allow-stderr, isolation-container