This script had #!/opt/slapos/parts/python2.7/bin/python2.7 which we
no longer ship.

This might be the reason why the test fail with an error like this in the log

    TASK [standalone-shared : Check ERP5 state] ************************************
    fatal: [127.0.0.1]: FAILED! => {"changed": true, "cmd": "/usr/local/bin/erp5-show -s", "delta": "0:00:00.003072", "end": "2022-09-01 22:49:43.877821", "failed": true, "rc": 127, "start": "2022-09-01 22:49:43.874749", "stderr": "/bin/sh: 1: /usr/local/bin/erp5-show: not found", "stdout": "", "stdout_lines": [], "warnings": []}

Goal: Fill a reference database in Wendelin for the OCEAN project.
How: Deploy a script in a Test Suite that scans and upload the desired parts of a KVM filesystem. This is a playbook for the deployment script.

Files: playbook/ridge.yml, playbook/roles/ridge/*

See merge request !163

See merge request !165

1.0.248 is the most recent version that is in binary cache

See merge request !161

It has more chances to exist than /usr/bin/python executable

This commit also simplifies the preparation of the cache for OBS compilation.

The slapos-node package can be built in any Linux distribution (old or
new).

WARNING: Do not use PYTHON make variable since it messes up with compilation. Instead
use SLAPOS_BOOTSTRAP_SYSTEM_PYTHON which explains the idea of the variable
and does not overrides make's PYTHON variable in other places.

also do not check for invalid certificate in slapos.cfg anymore. It's
been more than 3 years that the certificate is invalid. All our machines
are updated.

For CentOS_8 & CentOS_8_Stream, I give up:
- nothing provides python, python2, python3 or /usr/bin/python
  (actually, there's a python2 package on CentOS_8_Stream, but only to ship
  a /usr/bin/python2 that tells the user not to use Python 2... wtf ?)
- by default, there exists /usr/libexec/platform-python and it's functional
  but the build of openssl requires any of python{,2,3} in PATH, which means
  that a probable solution is to:
  - conditionally depend on 'python' only `%if 0%{?centos_ver} != 8`
  - change Makefile.in to add a symlink to /usr/libexec/platform-python
    in a temporary directory that we add to $PATH during the build
- ... but it's probably fine to use packages for CentOS_7

- Make it compatible with Python 3.
- Install setuptools in a way that's compatible with slapos.rebootstrap
  (otherwise, rebootstrapping fails because signature dependency to
  setuptools changes).

playbook: imt-vm-bootstrap playbook will be called only until success, then it is never called again

This reverts commit 910d2148.

Actually, we will simply stop executing the playbook totally after it is
well configured.

This reverts commit dd750800.