Add unit test the explicit tests create a GrVkCopyPipeline

Bug: skia:7663
Change-Id: I9883d903302fbbcd42f73601f49af96b6cc875ba
Reviewed-on: https://skia-review.googlesource.com/111361
Commit-Queue: Greg Daniel <egdaniel@google.com>
Reviewed-by: Hal Canary <halcanary@google.com>
3 files changed