Merge branch 'ds/path-walk-filters'

The "git pack-objects --path-walk" traversal has been integrated with several object filters, including blobless and sparse filters. * ds/path-walk-filters: path-walk: support `combine` filter path-walk: support `object:type` filter path-walk: support `tree:0` filter t6601: tag otherwise-unreachable trees pack-objects: support sparse:oid filter with path-walk path-walk: add pl_sparse_trees to control tree pruning path-walk: support blob size limit filter backfill: die on incompatible filter options path-walk: support blobless filter path-walk: always emit directly-requested objects t/perf: add pack-objects filter and path-walk benchmark pack-objects: pass --objects with --path-walk t5620: make test work with path-walk var