[clang-tools-extra] Add check 'cppcoreguidelines-use-enum-class' (PR #138282)

[Baranov Victor via cfe-commits]

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@@ -0,0 +1,35 @@
+.. title:: clang-tidy - cppcoreguidelines-use-enum-class
+
+cppcoreguidelines-use-enum-class
+================================
+
+Finds unscoped (non-class) ``enum`` declarations and suggests using
+``enum class`` instead.
+
+This check implements `Enum.3
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vbvictor wrote:

Going through more examples, I see that most of `cppcoreguidelines-pro-type` checks and a couple of others have link in the end, but others tend to have up front.

I genuinely prefer it up front because it's helpful to go to core-guideline after reading a brief description of the check.

https://github.com/llvm/llvm-project/pull/138282