[CT] Use "--use-temp-checkout" for pushk
[CT] Use "--use-temp-checkout" for pushk

Bug: skia:10960
Change-Id: I6ba917fab2cc11fc4f1bd2adee63bc9206d7dc6e
Reviewed-on: https://skia-review.googlesource.com/c/buildbot/+/337517
Reviewed-by: Ravi Mistry <9fa2e7438b8cb730f96b74865492597170561628@google.com>
Commit-Queue: Ravi Mistry <9fa2e7438b8cb730f96b74865492597170561628@google.com>

google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot