Allow pip to be installed in Suse SLE 15.6

In Suse SLE 15.6, ansible can be installed either from the OpenSuse
repo of from PackageHub.

The version installed from OpenSuse requires Python >= 3.10.
Thus, it depends on the modern Python (version 3.11) provided by the
Python 3 module, instead of on the Python provided by the base system
module (version 3.6).
Packages installed for the modern Python, such as pip, will have
python311 as a prefix instead of just Python.

On the other hand, the ansible version in PackageHub is older and
can be used with the older Python version.

Thus, we check if either version of the package is installed, and if
not we install the more modern from those available.

See merge request nexedi/slapos.core!647.