Installation scripts using upstream packages

Tasks

• Create installation scripts that install upstream packages into a system (Tor and OpenResty packages) for distros where they're available. These can be alternatives to the build scripts (eg. install-debian-bookworm.sh as the package counterpart for build-debian-bookworm.sh).
• Update CI to (also) test these installation scripts.
• Update documentation in how to use using Tor and OpenResty upstream packages through these scripts. Moved to #33.

Time estimation

• Complexity: very small (0.5 day)
• Uncertainty: low (x1.1)
• Reference (adapted)