[clang-tools-extra] [clang-tidy] Add parallel execution by default in 'run-clang-tidy' and 'clang-tidy-diff' (PR #149739)

[via cfe-commits]

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@@ -93,6 +93,10 @@ Improvements to clang-query
 Improvements to clang-tidy
 --------------------------
 
+- The ``run-clang-tidy.py`` and ``clang-tidy-diff.py`` scripts now run checks in
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EugeneZelenko wrote:

```suggestion
- The :program:`run-clang-tidy.py` and :program:`clang-tidy-diff.py` scripts now run checks in
```

https://github.com/llvm/llvm-project/pull/149739