[clang-tools-extra] [clang-tidy][NFC] Fix formatting issue in `clang-tidy` documentations (PR #168722)

[via cfe-commits]

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@@ -96,21 +96,22 @@ to be checked. The format is the following, without newlines:
 The functions are matched using POSIX extended regular expressions.
 *(Note: The regular expressions do not support negative* ``(?!)`` *matches.)*
 
-The ``reason`` is optional and is used to provide additional information about the
-reasoning behind the replacement. The default reason is ``is marked as unsafe``.
+The ``reason`` is optional and is used to provide additional information about
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EugeneZelenko wrote:

Should be in single `back-ticks` (option values). Same below.

https://github.com/llvm/llvm-project/pull/168722