Only verify skipped buckets if present to reflect skipped bucket changes in aosp/2153240.

Bug: 243764172
Test: ValueMetricsTests#testPullerAcrossBucketsWithActivation

Merged-In: Ib9c6955c16d80eb601535435839a23f3f3c15edc
Change-Id: Ib028003042a56af204e9c4555c5eee350598dfbd
1 file changed