[clang] [clang-tools-extra] [clang-tidy] Add new check: `readability-redundant-typename` (PR #161574)

[Baranov Victor via cfe-commits]

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@@ -0,0 +1,26 @@
+.. title:: clang-tidy - readability-redundant-typename
+
+readability-redundant-typename
+==============================
+
+Finds unnecessary uses of the ``typename`` keyword.
----------------
vbvictor wrote:

I think we better use `redundant`, same as in check name

```suggestion
Finds redundant uses of the ``typename`` keyword.
```
(please update other places)

https://github.com/llvm/llvm-project/pull/161574