[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
+    strategy:
+      matrix:
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boomanaiden154 wrote:

I don't think a matrix strategy makes too much sense given how long these jobs take. I think it makes more sense to build them serially, similar to the main linux CI container. I'd prefer to stay as consistent with that one as possible because I want to refactor the container build jobs into a common action soon.

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