Implement the prepare_bazel_test_env script am: 2178bb2de9 am: 8eb6bb443e am: 0fa3de4e84 am: 33631428e8

Original change: https://android-review.googlesource.com/c/platform/build/pesto/+/1677135

Change-Id: I9637598dac61040a6204e71e191b485144d621d0
tree: 1f4fb1e246017932b2da3d2fa21066b184195803
  1. experiments/
  2. OWNERS