[clang-tools-extra] [clang-tidy] Speed up/rewrite `bugprone-stringview-nullptr` (PR #192889)

[Victor Chernyakin via cfe-commits]

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@@ -2,7 +2,7 @@
 
 namespace std {
 
-using size_t = long long;
+using size_t = unsigned long long;
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localspook wrote:

Drive-by fix

https://github.com/llvm/llvm-project/pull/192889