Enable Default Sparse Serialization Format for Improved Performance

Enable automatic selection of the sparse serialization format by default. It improves performance. The format is supported since version 22.1. After this change, downgrading to versions older than 22.1 might not be possible. A downgrade may require to set ratio_of_defaults_for_sparse_serialization=0.9375 55153. You can turn off the usage of the sparse serialization format by providing the ratio_of_defaults_for_sparse_serialization = 1 setting for your MergeTree tables. #49631 (Alexey Milovidov).