GHA: Linux: don't track all supported distro versions

[Al2Klimov]

Instead just give a generic explanation per distro.

[julianbrost]

We don't support Raspberry Pi OS 11 anymore.

Why? https://github.com/Icinga/icinga2/blob/master/doc/02-installation.md.d/03-Raspberry-Pi-OS.md still exists and after all, it's only Debian arm64, so why is the Raspberry Pi OS support now different from the Debian support?

[Al2Klimov]

Sure, we still support Raspberry Pi OS.
We just don't support Raspberry Pi OS 11 anymore because of e.g. build time:

https://git.icinga.com/packages/tooling/ci-templates/-/merge_requests/79 "os.yml: build only latest Debian for ARM"

[julianbrost]

To me, all these version-specific comments feel like an unnecessary maintenance burden. Do they even provide a benefit compared to if there were generic comments stating that OpenSUSE is also supposed to test compatibility with SLES¹ for example?

icinga2/.github/workflows/linux.yml

Lines 24 to 40 in 4b884ea

	- amazonlinux:2
	- amazonlinux:2023
	- debian:11 # and Raspberry Pi OS 11
	- debian:12 # and Raspberry Pi OS 12
	- fedora:39
	- fedora:40
	- fedora:41
	- opensuse/leap:15.3 # SLES 15.3
	- opensuse/leap:15.4 # and SLES 15.4
	- opensuse/leap:15.5 # and SLES 15.5
	- opensuse/leap:15.6 # and SLES 15.6
	- rockylinux:8 # RHEL 8
	- rockylinux:9 # RHEL 9
	- ubuntu:20.04
	- ubuntu:22.04
	- ubuntu:24.04
	- ubuntu:24.10

Footnotes

1. I'm using SLES as an example because it's questionable if the Debian builds test much for Raspberry Pi OS at all, given that this workflow doesn't even build for the ARM architecture. ↩

[Al2Klimov]

You're right. If someone wants to check for support (packaging), they already have https://icinga.com/subscriptions/support-matrix/