[clang-tools-extra] [clang-tidy] Implement alphabetical order test (PR #166072)

[Baranov Victor via cfe-commits]

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@@ -0,0 +1,5 @@
+// RUN: %python %S/../../../clang-tidy/tool/clang-tidy-alphabetical-order-check.py -o %t.clang-tidy-checks-list.rst
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vbvictor wrote:

To me, CMake should only be used as project-configuration step, it shouldn't run any tests beside some library checking.

https://github.com/llvm/llvm-project/pull/166072