Add pre-upload Required Extensions check to trace sync script Add a check to make sure that a new ANGLE trace has been run through the retracer with the 'get_min_reqs` argument before uploading to CIPD. Bug: b/42266279 Change-Id: Id6f847faf22a42062ab189ea9bc7fb9c3506e66b Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/5860299 Reviewed-by: Cody Northrop <cnorthrop@google.com> Commit-Queue: Cody Northrop <cnorthrop@google.com>