[llvm] [GitHub][CI] Add clang-tidy premerge workflow (PR #154829)

[Aiden Grossman via llvm-commits]

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@@ -0,0 +1,345 @@
+#!/usr/bin/env python3
+#
+# ====- clang-tidy-helper, runs clang-tidy from the ci --*- python -*-------==#
+#
+# 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
+#
+# ==-------------------------------------------------------------------------==#
+
+import argparse
+import os
+import subprocess
+import sys
+from typing import List, Optional
+
+"""
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boomanaiden154 wrote:

Nit: File level docstrings normally go at the very top of the file (or below the license header). The first line should also be on the same line as the first quote block and be a brief description of the file.

https://github.com/llvm/llvm-project/pull/154829