MAR-192: Added support for Debian 12 Bookworm to wsgi_website role:

- Update list of Python packages that are installed for running the
tests.
- Paramterise Python version testing (depends on distribution
release). Use similar construct like for the php_website role.

MAR-191: Drop support for Debian 11 Buster from the wsgi_website role:

- Get rid of the workaround that used to cause issues in some of the
previous versions of Debian while at it. This should no longer pose
an issue.

MAR-151: Added support for Debian 10 Buster to wsgi_website role:

- Updated role reference documentaiton.
- Updated role meta information.
- Updated tests.
- Replace the installation of libmariadbclient-dev-compat library with
atftp - the actual package is differently named under Debian Stretch
and Debian Buster (which would complicate the test without any
benefits).
- Drop the fix for root mail alias in Vagrant image - seems it's no
longer a problem.
- Split-up the test for web application user since it's not possible
to keep it all under one parametrised test due to differences in
assigned system UID numbers for Debian Stretch and Debian Buster.
- Make the test for web application user less dependant on what the
actual UID number is in case of default value. By default user
should be created as system user, which means its UID number should
be less than 1000.

MAR-129: Updated wsgi_website role for Ansible 2.5.x and new Molecule:

- Include top-level linting configuration in test configuration file.
- Fixed linting errors.
- Updated Ansible deprecation warnings related to use of
state=installed with apt module.
- Updated how hosts are being referenced in tests.
- Rename the 'ss' utility in order to properly test socket
connectivity as a workaround for Testinfra bug.

MAR-128: Upgraded tests for ROLE_NAME role:

- Switch to new Molecule configuration.
- Updated set-up playbook to use become: yes.
- Moved some preparatory steps outside of the main playbook (eases
idempotence tests).
- Updated tests to reference the yml inventory file.
- Updated tests to use new fixture (host instead of individual ones).
- Switched to extracting hostname instead of hard-coding it in a
couple of tests.
- Fixed some linting issues.
- Updated one of the tests that depend on output of pip freeze due to
new versions of packages coming out.
- Updated hostname to include Debian version (for future expansion).
- Renamded some test data to match new hostname.