[clang-tools-extra] [clang-tidy] `modernize-use-trailing-return-type`: add an option to apply to `void`-returning functions as well (PR #129406)

[Baranov Victor via cfe-commits]

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@@ -25,6 +25,14 @@ transforms to:
   inline auto f2(int arg) -> int noexcept;
   virtual auto f3() const && -> float = delete;
 
+Options
+-------
+
+.. option:: WarnOnNontrailingVoid
+
+  If the option is set to `true`, the check will apply even to function signatures
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vbvictor wrote:

Please, make lines no more than 80 characters long.

https://github.com/llvm/llvm-project/pull/129406