Update CI Distro Matrix

[MichaelSimons]

Current CI Distro Matrix

6.0	8.0	9.0
Alpine 3.17	Alpine 3.19	Alpine 3.19
Debian 11
CentOS 7
	CentOS Stream 8
CentOS Stream 9	CentOS Stream 9	CentOS Stream 9
Fedora 38	Fedora 38	Fedora 39
Ubuntu 18.04	Ubuntu 22.04	Ubuntu 22.04

Proposed changes

6.0

• Drop Debian 11
• Upgrade Fedora 38 -> 40
• Ubuntu 18.04 -> 20.04

8.0

• Drop CentOS Stream 8
• Upgrade Fedora 38 -> 40

9.0

• Upgrade Fedora 39 -> 40
• Ubuntu 22.04 -> 24.04

Proposed CI Distro Matrix

6.0	8.0	9.0
Alpine 3.17	Alpine 3.19	Alpine 3.19
CentOS 7
CentOS Stream 9	CentOS Stream 9	CentOS Stream 9
Fedora 40	Fedora 40	Fedora 40
Ubuntu 20.04	Ubuntu 22.04	Ubuntu 24.04

[omajid]

Would it be possible to add a CentOS 8-like OS (Alma? Rocky?) to the matrix for 8.0 and/or 9.0?

[MichaelSimons]

[Triage] The point of @omajid's suggestion is to ensure SB builds on the lowest supported glibc version.

[MichaelSimons]

[Triage] We should ensure this proposal aligns with the CI policy and resolve any differences (either way).

[MichaelSimons]

The 6.0 runtime doesn't support Clang 18+ so 6.0 can only be built on Fedora 39 not Fedora 40. dotnet/runtime#100258 would need to be back ported if we wanted to support this. The .NET Fedora project has a patch to support this.

[omajid]

I submitted the Fedora patch to 6.0: dotnet/runtime#102529

[MichaelSimons]

I submitted the Fedora patch to 6.0: dotnet/runtime#102529

I am going to proceed with the Fedora 39 upgrade since I have everything tested and it includes other changes to get us off EOL distros. Once the runtime change is merged and flows in, I will upgrade.