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

- Some tweaks had to be done to test the TLS, but it would be useful
to revisit the TLS configuration in general in the future, and to
modernise it for TLSv1.2 and TLSv1.3, especially once the supports
for Debian 11 Bullseye is dropped.

MAR-189: Disable use of KVM paravirtualisation provider with Vagrant/VirtualBox:

- The VMs seem to randomly hang when the (KVM) clock source gets
initialised right after getting past the bootloader. Helps run the
tests in a way more reliable way.
- Should be removed if upgrading to latest kernel/VirtualBox versions
helps.

MAR-189: Refactored web_server tests to be less hostname-dependent:

- Use the inventory name (alongisde distribution version) in places
where it's possible and makes sense to do so.
- Rearrange the IP allocation a bit to make more sense.
- Drop architecture information from the hostnames.
- Make the connectivity test operate over a matrix of input
parameters.
- Replace singular use of wget for testing with curl.

MAR-181: Drop support for Debian 9 Stretch from web_server role:

- Switch to using IPs from VirtualBox default allowed host-only
network subnets.
- Drop Stretch-specific code and tests.

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

- Updated role reference documentaiton.
- Updated role meta information.
- Updated tests.
- Refactor the code around handling of different directories and files
for PHP 7.0 (Debian Stretch) and PHP 7.3 (Debian Buster).
- Separate socket directory tests for WSGI and PHP applications (due
to differences in paths for PHP in Debian Stretch and Debian
Buster).

MAR-150: Use fixtures for X.509 artefacts in the web_server role:

- Removed the statically generated artefacts.
- Generate X.509 artefacts for tests using Gimmecert.
- Updated paths to point to generated artefacts.
- Introduced cleanup playbook for removing generated artefacts.

MAR-148: Disable Ansible's default of enforcing group names without dashes through Molecule configuration files:

The following links might be a useful read:

- https://github.com/ansible/ansible/issues/56930 (issues relaetd to
lack of docs, but many complaints and explanations within)
- https://groups.google.com/forum/#!topic/ansible-devel/bjAcM9ferIw

MAR-132: Added support for Debian 9 (Stretch) to web_server role:

- Introduced internal parameters for controlling differing package
names, service names, and paths for PHP FPM package.
- Added Debian 9 machines to Molecule configuration, including the
client machine.
- Restructured slightly preparaiton playbook to support both Jessie
and Stretch.
- Added custom pytest fixture for having a better way to determine
expected package names etc related to PHP.
- Created copy of private key/certificate pair used for testing of
mandatory parameters (to be used with Stretch machine).
- Fixed invalid specification for hosts on top of which the
connectivity test should be run.
- Updated a couple of task names (avoiding to reference PHP 5).
- Updated documentation.

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

- Fixed linting errors.
- Include global linting configuration file in the test configuration.
- Moved variables from the test playbook into group variables.
- Updated how hosts are referenced in tests.
- Fixed deprecation warnings.

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.
- Renamed hosts instances to include Debian version in their
hostnames.
- Fixed some linting issues.