Update build-tools to ab/6869517 am: 48542e4070 am: 6e784c8963 am: bbf5892a0d

Original change: https://android-review.googlesource.com/c/platform/prebuilts/build-tools/+/1446781

Change-Id: I85ab5e3b4a3217dcd6ded09762d446d62ce99d74