add Release SkVMBlitter bot

Now that assert_true()  leads to different code generation
in Debug and Release builds, we should probably test both.

Cq-Include-Trybots: skia.primary:Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-All-SK_USE_SKVM_BLITTER,Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Release-All-SK_USE_SKVM_BLITTER
Change-Id: Icd3b67f09d964becb595ce9c95e7ebadae8da9b2
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/253898
Reviewed-by: Mike Klein <mtklein@google.com>
Commit-Queue: Mike Klein <mtklein@google.com>
Auto-Submit: Mike Klein <mtklein@google.com>
2 files changed