Reorg Support: Handling of orphaned blocks

[kuba-4chain]

Description of Changes

1. Handling of orphaned blocks was implemented
   • for each incoming block, a check is performed for orphaned chains that may be missing that block as a parent
   • if an orphaned chain is found and there is a fork of chains - the tip of that orphaned chain is being verified against the tip of current longest chain, instead of the incoming block
2. Unused orphadyned field was removed from database.
3. A transaction and a table lock (for table blocks) was introduced for block processing, so that only one block can be processed at a time. This allows for a simpler logic of this already quite complicated flow and avoids a lot of concurrency errors.
4. An integration test was refactored and updated to check most of possible edge cases regarding orphaned blocks handling.

Linked Issues / Tickets

#ARCO-199

Testing Procedure

Describe the tests you've added or any testing steps you've taken.

• I have added new unit tests
• All tests pass locally
• I have tested manually in my local environment

Checklist:

• I have performed a self-review of my own code
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have updated CHANGELOG.md with my changes