[infra] Update git, make [Canvas|Path]Kit et al use git from CIPD

These docker-based tests don't actually need a checkout, but removing it
is proving time consuming and syncs are timing out.

Probably related to skia:9588

Bug: skia:9588
Change-Id: I39532f1d9cd1f6116fab341e648a517b98a312c2
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/252156
Reviewed-by: Kevin Lubick <kjlubick@google.com>
Commit-Queue: Eric Boren <borenet@google.com>
2 files changed