[clang] [clang-tools-extra] [clangd] Use `SymbolName` to represent Objective-C selectors (PR #82061)

[Ben Barham via cfe-commits]

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@@ -13,6 +13,7 @@ add_clang_library(clangToolingRefactoring
   Rename/USRFinder.cpp
   Rename/USRFindingAction.cpp
   Rename/USRLocFinder.cpp
+  SymbolName.cpp
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bnbarham wrote:

Should `SymbolName.cpp` live in `Rename` to match its header?

https://github.com/llvm/llvm-project/pull/82061