[llvm][clang] Move a stray test into the Clang subdirectory
diff --git a/llvm/clang/test/Modules/implicit-opt-level.c b/clang/test/Modules/implicit-opt-level.c similarity index 100% rename from llvm/clang/test/Modules/implicit-opt-level.c rename to clang/test/Modules/implicit-opt-level.c