Improve chain connector storage

[ishantiw]

What was the problem?

This PR resolves #9195

How was it solved?

• Improve storage to retrieve by key/val and delete efficiently instead of managing full array
• Reduce number of RPC calls during new block event
• Improve cleanup
• Add tests

How was it tested?

• Run interop setup
• Register sidechains on mainchain and mainchain on sidechains.
• Make cross chain transfers using the scripts as mentioned in the readme
• Stop mainchain-node-two for more than 1000 blocks (mainchain-node-one generates the blocks) and then start it and see if it syncs properly and starts sending valid CCUs without any errors.

[codecov]

Codecov Report

Attention: Patch coverage is 79.24242% with 137 lines in your changes are missing coverage. Please review.

Project coverage is 83.28%. Comparing base (39c521f) to head (228050a).

❗ Current head 228050a differs from pull request most recent head 053a4e0. Consider uploading reports for the commit 053a4e0 to get more accurate results

Additional details and impacted files

@@               Coverage Diff                @@
##           hotfix/6.0.2    #9198      +/-   ##
================================================
- Coverage         83.52%   83.28%   -0.24%     
================================================
  Files               606      608       +2     
  Lines             22890    23101     +211     
  Branches           3377     3379       +2     
================================================
+ Hits              19118    19239     +121     
- Misses             3772     3862      +90     

Files	Coverage Δ
...ain-connector-plugin/src/chain_connector_plugin.ts	91.42% <100.00%> (+12.41%)	⬆️
...-framework-chain-connector-plugin/src/constants.ts	100.00% <100.00%> (ø)
...sk-framework-chain-connector-plugin/src/schemas.ts	100.00% <100.00%> (ø)
...lisk-framework-chain-connector-plugin/src/utils.ts	40.42% <100.00%> (-39.12%)	⬇️
...n-connector-plugin/src/active_validators_update.ts	93.75% <66.66%> (+13.39%)	⬆️
...ain-connector-plugin/src/certificate_generation.ts	95.65% <94.11%> (-2.31%)	⬇️
...amework-chain-connector-plugin/src/inbox_update.ts	95.65% <90.00%> (-4.35%)	⬇️
...k-framework-chain-connector-plugin/src/endpoint.ts	76.92% <90.47%> (-20.45%)	⬇️
...ramework-chain-connector-plugin/src/ccu_handler.ts	95.00% <95.00%> (ø)
...-chain-connector-plugin/src/block_event_handler.ts	87.64% <87.64%> (ø)
... and 2 more

... and 1 file with indirect coverage changes

[shuse2]

change in scope is quite big + im not fully understanding how plugin should work, so i might have missed something for the behavior.

Since it's plugin, i would assume as long as transaction is accepted on sidechain <=> mainchain scenario, it is fine