MAR-242: Mark some of the HTTP file sharing tests as slow:

- Update develpment instructions to include information on how to run
individual tests etc.

MAR-242: Added role parameters for xmpp_server role to configure HTTP file upload limits (XEP-0363):

- Refactor the daily quota tests to be a bit more flexible.

MAR-242: Refactor file upload tests:

- Use fixtures for grabbing the server host and cleaning up the
uploads directory. Deduplicates the test code a bit as well.

MAR-242: Added initial set of tests for file upload size and user daily quota:

- Tests currently operate on default values for the Prosody modules.

MAR-233: Replace hping3 with nmap in connectivity tests for the xmpp_server role:

- Parametrize the connectivity tests instead of running them in a
loop.

MAR-192: Switch to using go-sendxmpp where possible for testing XMPP server role:

- The sendxmpp in Debian 12 Bookworm is quite broken at this point,
and go-sendxmpp is somewhat close in terms of interface etc.
- Fix a number of tests related to sending messages.

MAR-189: Dropped deprecation-related tasks and tests for xmpp_server role:

- Migration from Prosody project repositories should have been done
already as part of the 7.0.1 release.
- Simplifies the code a bit.
- Drop leftover deprecated library plugin path.

MAR-181: Parametrise XMPP client tests:

- Reduces code duplication and makes it easier to expand list of
tested accounts.

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

- Updated tests to include Debian 9 in testing. Existing private keys
are reused where possible (since most of the naming is identical
between the machines with jessie/stretch).
- Updated invocation of sendxmpp in tests as workaround for
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=854210.
- Updated testing of imported keys to accomodate differences between
gpg/gpg2 (used by apt-key in Jessie/Stretch).

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

- Include top-level lint configuration in test configuration.
- Fixed linting errors.
- Moved test playbook variables into group_vars and host_vars.
- Fixed deprecation warnings from Ansible.
- Updated how hosts are referenced within tests.

MAR-128: Upgraded tests for xmpp_server 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 to include the Debian version.
- Updated names for some of the test data to cater to change in host
names.
- Switched to using more robust task for populating /etc/hosts.