ninjalog_uploader: fix command for Windows

Windows doesn't work with shebang.

Fixed: 1289707
Change-Id: I9db5f550d7ab5d2f92ccac392c3a5ee9595a9bf6
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/3406711
Auto-Submit: Takuto Ikuta <tikuta@chromium.org>
Reviewed-by: Fumitoshi Ukai <ukai@google.com>
Commit-Queue: Fumitoshi Ukai <ukai@google.com>

ninjalog_uploader_wrapper.py

@@ -58,11 +58,11 @@ The following information will be uploaded with ninjalog.
 Uploading ninjalog will be started after you run autoninja another %d time.
 
 If you don't want to upload ninjalog, please run following command.
-$ %s opt-out
+$ python3 %s opt-out
 
 If you want to allow upload ninjalog from next autoninja run, please run the
 following command.
-$ %s opt-in
+$ python3 %s opt-in
 
 If you have questions about this, please send mail to infra-dev@chromium.org