[llvm] workflows/build-ci-container: Add an arm64 container (PR #120828)

[Aiden Grossman via llvm-commits]

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@@ -33,8 +38,8 @@ jobs:
       - name: Write Variables
         id: vars
         run: |
-          tag=`date +%s`
-          container_name="ghcr.io/$GITHUB_REPOSITORY_OWNER/ci-ubuntu-22.04"
+          tag="${{ github.run_id}}.${{ github.run_attempt }}"
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boomanaiden154 wrote:

Ah, okay.

I think the short commit SHA would be better here given it makes things more easily searchable. Keeping the arch in the namespace sounds reasonable enough to me.

https://github.com/llvm/llvm-project/pull/120828