update_depot_tools: make cipd_bin_setup failures fatal
update_depot_tools: make cipd_bin_setup failures fatal

This should make them more noticeable.

Bug: 762568
Change-Id: Ibd4ca4dc34d36aec5773d28454d134c909cc78dc
Reviewed-on: https://chromium-review.googlesource.com/653157
Reviewed-by: Daniel Jacques <8400006a9338a0893dca0101ad49838955bd6b2c@chromium.org>
Commit-Queue: Paweł Hajdan Jr. <84cab74a96a175cf90ed68b8abab420352923e11@chromium.org>

CoherentLabs/depot_tools,CoherentLabs/depot_tools