Use Truth built from source. am: 108a0e1c1b

Original change: https://android-review.googlesource.com/c/platform/external/exoplayer/+/2288473

Change-Id: Ibec3033401f0f3b5466888938388afb6ff3f9ecf
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>