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

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@@ -0,0 +1,212 @@
+# Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+# See https://llvm.org/LICENSE.txt for license information.
+# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+# To run these tests:
+# python3 check-alphabetical-order_test.py -v
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zeyi2 wrote:

This file is currently not ready for review yet.

I need to do some refactoring and put it in `.ci/`

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