ci: various test updates

Assorted fixes and updates regarding tests.

Most important changes:

• bring deckard dependencies required by meson (for extra_tests) up-to-date
• add utility scripts for image rebuilds
• migrate pytests to LXC runners (and add a special image for it)

added tests label

Oh, file tests/README.rst isn't used in our sphinx-generated documentation set. That's... a bug?

marked this merge request as draft

added 18 commits

• 8666e239...bf9bf7bb - 10 commits from branch master
• 5b307a41 - meson: minor cleanup
• e5a50294 - tests: bring README up to date
• b3a1d2e6 - meson: update dependencies for deckard
• 16750e1a - ci/images: automate build&push of images
• a8c62d32 - gitignore: pytests junit xml files
• a5409990 - ci: omit extra dependencies for arm
• 1620ff06 - pytests: migrate to LXC runner
• 23884e27 - tests/README: merge with docs

Compare with previous version

resolved all threads

marked this merge request as ready

approved this merge request

added 17 commits

• 23884e27...da066e29 - 9 commits from branch master
• 1a9e7f3a - meson: minor cleanup
• 65ad94d3 - tests: bring README up to date
• 0fdd86e8 - meson: update dependencies for deckard
• 9bc815f7 - ci/images: automate build&push of images
• d0c3303d - gitignore: pytests junit xml files
• 2b44a10e - ci: omit extra dependencies for arm
• 15c13535 - pytests: migrate to LXC runner
• d952452d - tests/README: merge with docs

Compare with previous version

merged

mentioned in commit 8ac59353