[libcxx-commits] [libcxx] [libcxx] Update docs for updating the CI container image (PR #226018)

[Louis Dionne via libcxx-commits]

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@@ -274,32 +274,18 @@ GCC, and CMake.
 Updating the CI testing container images
 ----------------------------------------
 
-The libcxx linux premerge testing can run on one of three sets of runner
-groups. The three runner group names are ``llvm-premerge-libcxx-runners``,
-``llvm-premerge-libcxx-release-runners`` and ``llvm-premerge-libcxx-next-runners``.
-The runner set currently in use is controlled by the contents of
-https://github.com/llvm/llvm-project/blob/main/.github/workflows/libcxx-pr-conformance-tests.yaml.
-By default, it uses ``llvm-premerge-libcxx-runners``. To switch to one of the
-other runner sets, just replace all uses of ``llvm-premerge-libcxx-runners`` in
-the yaml file with the desired runner set.
-
-The container image used by these three runner sets is controlled by the contents
-of the corresponding text files in ``libcxx/utils/ci/images``. The content of these
----------------
ldionne wrote:

We should also remove `libcxx/utils/ci/images/libcxx_next_runners.txt` and its friends.

https://github.com/llvm/llvm-project/pull/226018