Generate interleavings in MetadataSegmentManager.markAsUnusedAllSegmentsInDataSource()

If `MetadataSegmentManager.markAsUnusedAllSegmentsInDataSource()` is called for a large data source, it may hang up the SQL table for some time. The code may generate interleavings and update only, say, 1000 entries at a time, and sleep between these "batches" for several seconds.

Start at MetadataSegmentManager.markAsUnusedAllSegmentsInDataSource() and inspect how it currently updates segments for a large data source. Determine how batching, interleaving, and pauses should fit the existing operation. Done means large-data-source calls update bounded batches with pauses instead of holding up the SQL table for an extended period.

Written by the indexing model from the issue text.