To query the current version to instead of the fixed value

The version of the apk in the shim apex is a fixed value. To query
the currernt version from the system to instead of the fixed value.

Test: atest CtsRollbackManagerHostTestCases
Fix: 154927160
Change-Id: I330e88784279a4078b5a685101f624b8e7278df6
Merged-In: I330e88784279a4078b5a685101f624b8e7278df6