qa: barbican: restrict python packages with upper-constraints

qa: barbican: restrict python packages with upper-constraints

We install barbican by doing a pip install directly on the
cloned git repository but we don't honor the upper-constraints
from the OpenStack Requirements project that handles what
versions is supported.

This changes the pip install command that we issue when
installing barbican to honor the requirements for the
version (derived from the branch) that we use, in
this case it's the 2023.1 release upper-constraints [1].

This prevents us from pulling in untested Python packages.

This only updates Barbican because for the Keystone job
we dont directly issue pip but install using tox using the
`venv` environment which already by default sets the
constraints as you can see in [2].

[1] https://releases.openstack.org/constraints/upper/2023.1
[2] https://github.com/openstack/keystone/blob/stable/2023.1/tox.ini#L12

Fixes: https://tracker.ceph.com/issues/67444
Signed-off-by: Tobias Urdin <tobias.urdin@binero.com>