[core] Adjust cw<3.21 compatibility
Most of cubibweb < 3.21 expects a ClientConnection as the main connection.
Related to #5731814
Closes #5878592
.. _core_module:
:mod:`pyramid_cubicweb.core`
----------------------------
.. automodule:: pyramid_cubicweb.core
.. autofunction:: includeme
.. autofunction:: cw_to_pyramid
.. autofunction:: render_view
.. autofunction:: repo_connect
.. autofunction:: get_principals
.. autoclass:: CubicWebPyramidRequest
:show-inheritance:
:members:
.. autofunction:: _cw_session
.. autofunction:: _cw_cnx
.. autofunction:: _cw_request