Add UpdateAttempterIntegrationTesting am: 3fe496491e am: 62a1b1bcca am: 62416a0b6a

Original change: https://android-review.googlesource.com/c/platform/system/update_engine/+/1845834

Change-Id: I8fe15c615ab675ca768c2ca9e8e41a0f04c1d862