[clang-tools-extra] [clang-tidy] Add a new check 'performance-string-view-conversions' (PR #174288)

[Victor Chernyakin via cfe-commits]

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@@ -0,0 +1,92 @@
+// RUN: %check_clang_tidy -std=c++20 %s performance-string-view-conversions %t -- \
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localspook wrote:

Since the check works in C++17 and up, we should test it in all those versions
```suggestion
// RUN: %check_clang_tidy -std=c++17-or-later %s performance-string-view-conversions %t -- \
```

https://github.com/llvm/llvm-project/pull/174288