v1.6.9

Substreams

• Fix an issue preventing proper detection of gzip compression when multiple headers are set (ex: python grpc client)
• Fix an issue preventing some tier2 requests on last-stage from correctly generating stores. This could lead to some missing "backfilling" jobs and slower time to first block on reconnection.
• Fix a thread leak on cursor resolution resulting in bad counter for active connections
• Add support for zstd encoding on server