Is your feature request related to a problem?/Why is this needed

Currently the testing tool snapshot-metadata-lister only lists the changed blocks.
There needs to be a way to verify end to end the working of changed block tracking framework.

Describe the solution you'd like in detail

A verify functionality that works as follows:

• GetMetadataAllocated:
  • source-device: restored PVC from the target snapshot
  • target-device: fresh PVC
  • verify: this function would copy the changed blocks returned from the csi-driver from source-device to the target device and then compares both the devices to make sure there's no differences.
• GetMetadataDelta:
  • source-device: restored PVC from the target snapshot
  • target-device: restored PVC from the base snapshot
  • verify: this function would copy the changed blocks returned from the csi-driver from source-device to the target device and then compares both the devices to make sure there's no differences.

Describe alternatives you've considered

The above approach seems like the best way to test changed block tracking framework end to end without knowing the
internals of a storage system.

Additional context