[clang-tools-extra] [clang-tidy] Add performance-redundant-lookup check (PR #125420)

[Balazs Benics via cfe-commits]

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+.. title:: clang-tidy - performance-redundant-lookup
+
+performance-redundant-lookup
+============================
+
+This check warns about potential redundant container lookup operations within
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steakhal wrote:

Fixed in d9d3984a056192b8ef61f385090d90c55774123d

https://github.com/llvm/llvm-project/pull/125420