Allow inspection of current core storage-format version

[johnkerl]

This is not identical to the core version. Note that format version may or may not bump when core bumps a minor.

TileDB-Py snippet:

import tiledb
import numpy as np

schema = tiledb.ArraySchema(
    domain=tiledb.Domain(tiledb.Dim(name="rows", domain=(1, 4), dtype=np.int32)),
    attrs=[tiledb.Attr(name="a", dtype=np.int32)],
    sparse=False,
)

print(schema.version)

We can do similar in tiledbsoma.