os.rename --> os.replace (#21628)

Author: ravisumit33

tools/link.py

@@ -454,7 +454,7 @@ def make_js_executable(script):
 
 
 def do_split_module(wasm_file, options):
-  os.rename(wasm_file, wasm_file + '.orig')
+  os.replace(wasm_file, wasm_file + '.orig')
   args = ['--instrument']
   if options.requested_debug:
     # Tell wasm-split to preserve function names.