Updated ms-buildings

[TomAugspurger]

This updates the ms-buildings collection for some recent data and STAC metadata updates / changes.

The newest set of data (2023-04-25) have been rewritten in delta format, which offers scalable metadata handling (specifically partitioning and statistics, which can speed up access times to avoid touching large numbers of files in Blob Storage).

I've added a link to the delta table as a new collection-level asset (will update the example notebook shortly)

This also updates to the latest version of stactools-msbuildings, which

1. targets quadkey level items, rather than region level. This will make spatial searchers more useful
2. adds an msbuildings:processing-date property

Finally, I've added a pctasks task for creating the STAC items. Older items were created out of band and imported using the premade STAC item collection.

Note that this required slightly updating pctasks' chunk options to add a min_depth argument to pass through to walk.

[TomAugspurger]

This is ingested, and microsoft/PlanetaryComputerExamples#261 has an example using the new features.