Unknown geometry type: GEOMETRY with non-spatial GPKG

[wonder-sk]

This error can happen when using db-sync and doing init from gpkg - after the import of data to "modified" schema, the copy from "modified" schema to "base" schema can fail like this:

The base and modified schemas do not exist yet, going to initialize them ...
GEODIFF: NOTICE:  schema "dbsync_nonspatial" does not exist, skipping

Error: copy failed!
GEODIFF: Error: Unknown geometry type: GEOMETRY

This happens when there's just non-spatial table in the whole GPKG: in order to honor Requirement 17 from GPKG v1.1.0, OGR adds an empty table called ogr_empty_table when writing GPKG (this requirement has been dropped in GPKG v1.2.0).

The workaround for now is to skip that special table, but it would be nice to handle this properly.