[llvm] [Github][CI] Add separate container for code-format premerge job (PR #161083)

[Aiden Grossman via llvm-commits]

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@@ -0,0 +1,118 @@
+name: Build CI Container
+
+permissions:
+  contents: read
+
+on:
+  push:
+    branches:
+      - main
+    paths:
+      - .github/workflows/build-ci-container-tooling.yml
+      - '.github/workflows/containers/github-action-ci-tooling/**'
+      - llvm/utils/git/requirements_formatting.txt
+      - llvm/utils/git/requirements_linting.txt
+  pull_request:
+    paths:
+      - .github/workflows/build-ci-container-tooling.yml
+      - '.github/workflows/containers/github-action-ci-tooling/**'
+      - llvm/utils/git/requirements_formatting.txt
+      - llvm/utils/git/requirements_linting.txt
+
+jobs:
+  build-ci-container-tooling:
+    if: github.repository_owner == 'llvm'
+    runs-on: depot-ubuntu-24.04-16
----------------
boomanaiden154 wrote:

We should have a step like https://github.com/llvm/llvm-project/blob/30b9b2823919631ca12d6655792c4e80c7ba6679/.github/workflows/libcxx-build-containers.yml#L37. Using 64 core machines to download and unpack archives is a huge waste.

https://github.com/llvm/llvm-project/pull/161083