run-clang-tidy.py should only search for the clang-apply-replacements if really needed

[aabhinavg]

Summary

run-clang-tidy.py should only search for the clang-apply-replacements if really needed.

[carlosgalvezp]

LGTM, clang_apply_replacements_binary is only used in a if args.fix block.

clang-tools-extra/clang-tidy/tool/run-clang-tidy.py

def main():
   else:
     # Find our database
     build_path = find_compilation_database(db_path)
 
   clang_tidy_binary = find_binary(args.clang_tidy_binary, "clang-tidy",
                                   build_path)
 
   tmpdir = None
-  if args.fix or (yaml and args.export_fixes):
+  if args.fix:
     clang_apply_replacements_binary = find_binary(
       args.clang_apply_replacements_binary, "clang-apply-replacements",
       build_path)
     tmpdir = tempfile.mkdtemp()
 
   try:
     invocation = get_tidy_invocation("", clang_tidy_binary, args.checks,
                                      None, build_path, args.header_filter,