Set skia_use_vulkan on our vulkan bots.

Bug: skia:
Change-Id: Ia7cdab1223ae3eb788e46e2cc4af552b03a2065f
Reviewed-on: https://skia-review.googlesource.com/c/181163
Commit-Queue: Greg Daniel <egdaniel@google.com>
Commit-Queue: Ben Wagner <benjaminwagner@google.com>
Auto-Submit: Greg Daniel <egdaniel@google.com>
Reviewed-by: Ben Wagner <benjaminwagner@google.com>
4 files changed