[clang-tools-extra] Add clang-tidy external examples (PR #106675)

[Julian Schmidt via cfe-commits]

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@@ -5,21 +5,22 @@ External Clang-Tidy Examples
 Introduction
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-This page provides examples of what people have done with clang-tidy that 
+This page provides examples of what people have done with `clang-tidy`` that 
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5chmidti wrote:

unintended double backtick

https://github.com/llvm/llvm-project/pull/106675