[clang-tools-extra] [llvm] [Github][CI] Add `doc8` for clang-tidy documentation formatting (PR #168827)

[Baranov Victor via llvm-commits]

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@@ -71,25 +71,41 @@ jobs:
                 -DLLVM_INCLUDE_TESTS=OFF \
                 -DCLANG_INCLUDE_TESTS=OFF \
                 -DCMAKE_BUILD_TYPE=Release
-          
+
           ninja -C build \
                 clang-tablegen-targets \
                 genconfusable               # for "ConfusableIdentifierCheck.h"
 
-      - name: Run code linter
+      - name: Install linter dependencies
+        run: pip install doc8 --break-system-packages
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vbvictor wrote:

Oh I forgot to change package visibility from private to public, now it should work as intended.

> And I think for the CI jobs after merging to actually use this, we need to push the Dockerfile update to main for the container becomes public, right?

As soon as we push container to main, [this job](https://github.com/llvm/llvm-project/actions/workflows/build-ci-container-tooling.yml) rebuild and update container, so `code-lint:latests` will be ready automatically in around 15 mins. There would be a gap when CI won't work, but IMO it's negligible.
I think we can do it in one go.

https://github.com/llvm/llvm-project/pull/168827