[llvm] [CI] Upstream metrics script and container definition (PR #117461)

[Tom Stellard via llvm-commits]

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@@ -0,0 +1,7 @@
+FROM python:3.12
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tstellar wrote:

I prefer using the full URL for the base image so we know exactly where the container is coming from.

https://github.com/llvm/llvm-project/pull/117461