Update README with additional instructions am: 7fc3494f6a am: 784267f9ed

Original change: https://android-review.googlesource.com/c/platform/build/pesto/+/1701745

Change-Id: Id7d703c461e55dc63ac00c1c30de8bd49adbb6f5
tree: 2ae08a33bf0b0ba28b3a33a9315795a8689b0499
  1. experiments/
  2. OWNERS