Stop using compression for git cache update bootstrap.
Stop using compression for git cache update bootstrap.

Change git cache to stop zipping the git directory and instead upload directly to GS.

Bug: 943696
Change-Id: I310fb48ff3d7fd6781914e14e0e17530d5d9b328
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/1585029
Commit-Queue: Karen Qian <cca779e1ec38fb5b6daaa25edee84281b543e630@google.com>
Reviewed-by: Andrii Shyshkalov <a30c74fa30536fe7ea81ed6dec202e35e149e1fd@chromium.org>

CoherentLabs/depot_tools,CoherentLabs/depot_tools