[infra] Add explicit DEPS entry for infra repo

I'm going to unify all of the infra stuff that rolls into skia, using
'infra_revision' as the source of truth.

Change-Id: I1c33d7a3dc7b1c47d0a3e6046af4ba4ff6688161
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/896462
Reviewed-by: Kaylee Lubick <kjlubick@google.com>
Commit-Queue: Eric Boren <borenet@google.com>
2 files changed