[7.0] Remove centos 8 images

[carlossanlop]

We're seeing failures in 7.0 queues due to using non-existent centos 8 images.

Sending directly to the base branch so it gets automatically synced to internal and staging after merging.

cc @jozkee @krwq

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Issue Details

---

We're seeing failures in 7.0 queues due to using non-existent 16.04 images.

Sending directly to the base branch so it gets automatically synced to internal and staging after merging.

cc @jozkee @krwq

Author:	carlossanlop
Assignees:	carlossanlop
Labels:	area-Infrastructure
Milestone:	-

[hoyosjs]

While I don't have a strong opinion about this change - the kernel in 18.04 is much newer and we'd lose some back coverage for test matrix of what's supported. Helix shows the queue existing. Do you have a link to the build?

[hoyosjs]

The real problem is centos8 is EOL. We haven't tested it in any significant manner. This needs to be closer to:

runtime/eng/pipelines/coreclr/templates/helix-queues-setup.yml

Lines 105 to 109 in 29d485c

	- ${{ if eq(parameters.platform, 'linux_x64') }}:
	- ${{ if eq(variables['System.TeamProject'], 'public') }}:
	- Ubuntu.1804.Amd64.Open
	- ${{ if eq(variables['System.TeamProject'], 'internal') }}:
	- Ubuntu.1804.Amd64

It's not great we aren't testing ~16.04 kernels IMO, but at the very least I am OK with removing a couple of these queues. Also, we haven't tested CI in internal for a long time - only PR builds. So they should somewhat mimic PRs on main to have a baseline comparison. This applies for all the entries in this yml - Jeremy had updates this in main, but we never fixed servicing.

[hoyosjs]

The real problem is centos8 is EOL. We haven't tested it in any significant manner. This needs to be closer to:

runtime/eng/pipelines/coreclr/templates/helix-queues-setup.yml

Lines 105 to 109 in 29d485c

	- ${{ if eq(parameters.platform, 'linux_x64') }}:
	- ${{ if eq(variables['System.TeamProject'], 'public') }}:
	- Ubuntu.1804.Amd64.Open
	- ${{ if eq(variables['System.TeamProject'], 'internal') }}:
	- Ubuntu.1804.Amd64

It's not great we aren't testing ~16.04 kernels IMO, but at the very least I am OK with removing a couple of these queues. Also, we haven't tested CI in internal for a long time - only PR builds. So they should somewhat mimic PRs on main to have a baseline comparison. This applies for all the entries in this yml - Jeremy had updates this in main, but we never fixed servicing.