Fix FileExistsError on subsequent bazel builds on Windows (#1326) (#1326)

Fixes #1181.

bazel/emscripten_toolchain/link_wrapper.py

diff --git a/bazel/emscripten_toolchain/link_wrapper.py b/bazel/emscripten_toolchain/link_wrapper.py
index d6b715d..ca6ca48 100644
--- a/bazel/emscripten_toolchain/link_wrapper.py
+++ b/bazel/emscripten_toolchain/link_wrapper.py
@@ -61,7 +61,7 @@
 
   # If the output name has no extension, give it the appropriate extension.
   if not base_name_split[1]:
-    os.rename(output_file, output_file + '.' + oformat)
+    os.replace(output_file, output_file + '.' + oformat)
 
   # If the output name does have an extension and it matches the output format,
   # change the base_name so it doesn't have an extension.
@@ -77,7 +77,7 @@
   # Please don't do that.
   else:
     base_name = base_name_split[0]
-    os.rename(output_file, os.path.join(outdir, base_name + '.' + oformat))
+    os.replace(output_file, os.path.join(outdir, base_name + '.' + oformat))
 
 files = []
 extensions = [
@@ -161,6 +161,6 @@
 # cc_binary must output exactly one file; put all the output files in a tarball.
 cmd = ['tar', 'cf', 'tmp.tar'] + files
 subprocess.check_call(cmd, cwd=outdir)
-os.rename(os.path.join(outdir, 'tmp.tar'), output_file)
+os.replace(os.path.join(outdir, 'tmp.tar'), output_file)
 
 sys.exit(0)