[FLINK-35510][statebackend] Implement basic incremental checkpoint fo…

[zoltar9264]

…r ForStStateBackend

What is the purpose of the change

Use low DB api implement a basic incremental checkpoint for ForStStatebackend, follow steps:

1. db.disableFileDeletions()
2. db.getLiveFiles(true)
3. db.entableFileDeletes(false)

Brief change log

• Introduce ForStStateDataTransfer
• Introduce ForStIncrementalSnapshotStrategy

Verifying this change

This change added tests and can be verified as follows:

• Added test ForStStateDataTransferTest
• Added test ForStIncrementalSnapshotStrategyTest

Does this pull request potentially affect one of the following parts:

• Dependencies (does it add or upgrade a dependency): (no)
• The public API, i.e., is any changed class annotated with @Public(Evolving): (no)
• The serializers: (no)
• The runtime per-record code paths (performance sensitive): (no)
• Anything that affects deployment or recovery: JobManager (and its components), Checkpointing, Kubernetes/Yarn, ZooKeeper: (no)
• The S3 file system connector: (no)