MAR-192: Fix incorrect prompt for pipreqcheck virtual environment:

- Ensure that the virtualenv indicator string ends with a
whitespace.
- The virtualenv prompt parameter behaves slightly different between
the versions of Debian 11 Bullseye and Debian 12 Bookworm - the former
being a bit more user-friendly.
- Recreate virtual environment if the prompt does not match-up.

MAR-192: Drop the Python 2.7-specific packages from installation:

- These are leftovers from previous work for dropping the Python 2.7
support.

MAR-154: Update documentation and test site for Python 2.7 support removal:

- Drop most of the references to Python 2.
- Switch anything that has been previously using Python 2.7 to Python
3.

MAR-154: Drop support for Python 2.7 from the common role:

- This primarily concerns removal of pip requirements upgrade checks
for Python 2.7.
- The old Python 3-specific paths are getting deprecated, and the
Python 2 paths will be used instead.
- Set permissions on pipreqcheck directory explicitly (because of
deprecation testing).

MAR-191: Drop support for Debian 10 Buster from the common role:

- Fix incorrect comment on the pkg-resources/pkg_resources package as
well - this one is not distro-dependent.

MAR-189: Rework fix for legacy iptables and ferm:

- Unfortunately, using diversions with iptables legacy binaries does
not work correctly because the iptables package will try to run
update-alternatives on install/upgrade, and error out because the
files are not available in the original locations.
- Divert the ferm binary instead, and roll-out a custom patched
version of it instead.
- Use a custom script to drop the legacy iptables (for both IPv4 and
IPv6).
- Update the tests accordingly.

MAR-189: Disable the legacy iptables tools by effectively renaming them:

- Somewhat more forceful but better way to deal with ferm in Bullseye
explicitly using the legacy tools for some unspecified compatibility
reasons.
- Renders the tools unusable because the calling name has
changed (they are all symlinks to the same file).
- Not necessarily required on Debian Buster, but it also won't cause
any damage there either.

MAR-189: Added support for Debian 11 Bullseye to common role:

- Drop the architecture suffix from all machines.
- Introduced a hack/patch for Ferm utility that disables use of legacy
iptables tools.
- Minor fixes around package name differences compared to older
distribution.
- Use versioned binary name for Python 2.7.. Bullseye does not
default/have /usr/bin/python pointing to Python 2.7 binary.

MAR-184: Update package versions for pip upgrade checks virtual environments:

- Should provide better test coverage compared to previously since
newer versions of pip-tools have slightly different ways of resolving
packages, as well as output formats.

MAR-151: Drop rcconf workaround:

- The workaround was needed on Debian Jessie because the systemctl
is-enabled command did not behave correctly for SysV init scripts.
- Drop the installation of the rcconf package.
- Use the "enabled" parameter in service module instead.

MAR-163: Ensure host.run is not suspectible to shell injection:

- Use host.run's built-in capability for handling parameter escaping
and insertion.

MAR-149: Minor syntax fixes for Python 3 in tests for common role:

- Do not use the unicode function (this still might break, need to
test it).
- Fix syntax used for catching exceptions within variables.
- Fix one small linting error related to row length.

MAR-149: Switch to using File.content_string instead of File.content in tests for all roles:

- The .content variant returns contents as bytes, while the
content_string returns a string (which is what is wanted in
practically all cases).

MAR-148: Clean-up TODO entries for the common role coming from bugs in earlier versions of software:

- Switch to using the systemd task for reloads.
- Add back validation of pipreqcheck activation script file
permissions.
- Add back validation of missing ntp/ntpdate packages.

MAR-148: Fix test for the common role:

- Do some additional stripping on command outputs to get rid of extra
new lines.

MAR-146: Added separate parameter for Pyhton 3 virtual environment used for upgrade checks:

- Release notes updated to mention the breaking change.
- Updated role reference documentation to cover the new parameter.
- Updated default values for the dedicated Python virtual
environments.
- Update role common to deploy separate requirements for the two
environments.
- Include wheel package in the requirements.

MAR-141: Fix handling of pipreqcheck virtualenv package installation:

- Deploy all requirements through requirements file, even if using
pip. Improves reproducability of installed packages and solves some
double-versioning issues for packages like pip etc.
- Updated test for validating installed packages.

MAR-134: Make sure the Python setuptools are available for virtualenv use:

- Must be present for pipreqcheck virtual environments to get setup
correctly.
- Should be a good idea to include it in the default web server config
too.

MAR-129: Updated backup_server role tests:

- Move the 'ss' utility out of place in order to be able to test if
sockets are
open (seehttps://github.com/philpep/testinfra/pull/320).
- Updated tests to use correct mechanism for setting-up list of
machines where the tests should be run.

MAR-128: Upgraded tests for common role:

- Switch to new Molecule configuration.
- Updated set-up playbook to use become: yes.
- Moved some preparatory steps outside of the main playbook (easies
idempotence tests).
- Updated tests to reference the yml inventory file.
- Updated tests to use new fixture (host instead of individual ones).
- Switched to extracting IP address instead of hard-coding it in a
couple of tests.
- Fixed invalid indentation on task responsible for creating the
pipreqcheck Python virtual environment.