Clickhouse Sink deprecate, refactor & improvements

[DenisCarriere]

• [x] https://github.com/pinax-network/substreams-sink-clickhouse/issues/111
• [x] https://github.com/pinax-network/substreams-sink-clickhouse/issues/110
• [x] add exit handling
  • flush buffer on exit
• [x] Convert buffer to in-memory instead of SQLite
• [x] add module_hash to blocks TABLE
  • add module_hash query to /blocks
• [x] Ed25519 public key validation (check length)
• [x] add optimize to /blocks enpdoint (how many duplicate blocks that need to be optimized)
  • OPTIMIZE TABLE blocks FINAL
• [x] implement file based buffer (buffer.txt)