[NFC] Fixes -Wrange-loop-analysis warnings

This avoids new warnings due to D68912 adds -Wrange-loop-analysis to -Wall.

Differential Revision: https://reviews.llvm.org/D71857
diff --git a/clang/tools/clang-refactor/TestSupport.cpp b/clang/tools/clang-refactor/TestSupport.cpp
index cfe9c0c..617a671 100644
--- a/clang/tools/clang-refactor/TestSupport.cpp
+++ b/clang/tools/clang-refactor/TestSupport.cpp
@@ -74,7 +74,7 @@
                     const tooling::AtomicChanges &RHS) {
   if (LHS.size() != RHS.size())
     return false;
-  for (const auto &I : llvm::zip(LHS, RHS)) {
+  for (auto I : llvm::zip(LHS, RHS)) {
     if (!(std::get<0>(I) == std::get<1>(I)))
       return false;
   }