Don't supress failures in adopting shell permission identity.

This is required as we've seen recent flakiness in our tests where
the only way to find out the root cause (DeadObjectException when
adopting permissions) is to look in logcat.

Test: btest CtsDevicePolicyTestCases
Bug: 262371074
Change-Id: I2291984c77494a4afca0e403938e75cab1363ba6