[infra] Add pre-built bazel_build task driver to DEPS, add deps package

The deps package makes DEPS entries available in Go code, eg. gen_tasks.

Autorollers will need to be updated to keep deps_gen.go in sync.

Bug: b/362481036
Change-Id: Ib19ba907ee389445f9f7c0ca5fc593f3d487b1dd
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/894477
Commit-Queue: Eric Boren <borenet@google.com>
Reviewed-by: Kaylee Lubick <kjlubick@google.com>
8 files changed