[llvm] Use container on Linux to run llvm-project-tests workflow (PR #81349)

[Aiden Grossman via llvm-commits]

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@@ -58,6 +58,10 @@ jobs:
   lit-tests:
     name: Lit Tests
     runs-on: ${{ matrix.os }}
+    container:
+      image: ${{(startsWith(matrix.os, 'ubuntu') && format('ghcr.io/{0}/ci-ubuntu-22.04:latest', github.repository_owner)) || null}}
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boomanaiden154 wrote:

Why is this set to pull from the repository owner rather than just the container in upstream? I would think we would always want to use the container for upstream, even for testing to prevent having to run the (now eight hour) job on your fork to upload the package there.

https://github.com/llvm/llvm-project/pull/81349