[clang-tools-extra] [clang-tidy][docs] Remove obsolete doc8 instructions. NFC. (PR #210576)

[via cfe-commits]

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@@ -466,24 +466,7 @@ generator and create HTML documentation files in the
 ``tools/clang/tools/extra/docs/html`` directory in your build tree.
 Make sure that your check is correctly shown in the release notes and the list
 of checks. Make sure that the formatting and structure of your check's
-documentation look correct: there is no trailing whitespaces and lines are no
-longer than 80 characters.
-
-To validate your files, please use ``doc8`` as described below.
-
-Clang-Tidy uses `doc8 <https://pypi.org/project/doc8/>`_ to check ``.rst``
-files for formatting consistency. You can install ``doc8`` with ``pip``:
-
-.. code-block:: console
-
-  $ pip install doc8
-
-To run ``doc8`` on the modified documentations:
-
-.. code-block:: console
-
-  $ git diff --name-only HEAD -- clang-tools-extra/docs/clang-tidy/ | grep "\.rst$" | xargs -r doc8
-
+documentation look correct and contain no trailing whitespace.
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EugeneZelenko wrote:

Maybe dedicated script should be implemented? I doubt that training whitespaces make sense in Markdown.

https://github.com/llvm/llvm-project/pull/210576