This updates local reference to origin/HEAD, which is necessary for
new-branch to work as expected.

R=ehmaldonado@google.com

Change-Id: Ia620b3b01c0ad23bb4e969f9026fa6bcfdd88b90
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/2730051
Commit-Queue: Josip Sokcevic <sokcevic@google.com>
Auto-Submit: Josip Sokcevic <sokcevic@google.com>
Reviewed-by: Edward Lesmes <ehmaldonado@chromium.org>