Bump cipd client version.

New version skips unnecessary hash check for files that are already
in the cache.

R=iannucci@chromium.org
BUG=

Change-Id: Icdbd1d171fa77cf7e353c84e82ded8eafd88c88d
Reviewed-on: https://chromium-review.googlesource.com/454241Reviewed-by: Robbie Iannucci <iannucci@chromium.org>
Commit-Queue: Vadim Shtayura <vadimsh@chromium.org>

cipd_client_version

-git_revision:b1fb723fc4ce6d0b8167ecf4cac327386380d74b
+git_revision:76eadcd75c5ad2638e1fc098f81748aad150c7c0