[clang-tools-extra] [clang-tidy] Add more constexpr options to `readability-identifier-naming` (PR #162160)

[via cfe-commits]

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@@ -381,6 +381,10 @@ Changes in existing checks
   declarations and macros in system headers. The documentation is also improved
   to differentiate the general options from the specific ones.
 
+- Improved :doc:`readability-identifier-naming
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EugeneZelenko wrote:

I think sentence like `Options for fine-grained control over ``constexpr`` variables were added` should be appended.

https://github.com/llvm/llvm-project/pull/162160