gpkg_geometry_columns test needs to be updated

[jyutzler]

The ATS for /opt/features/geometry_columns/data/table_def calls for an inspection of the table SQL. Better would be to inspect the table itself through a PRAGMA table_info('gpkg_geometry_columns') command as is done in /opt/features/vector_features/data/feature_table_integer_primary_key.

In addition the reference C.4Table 20 appears to be wrong. If anything it should be C.3 but really it should refer back to the table the requirement points to. However, Table 7 does not indicate that the columns may not be null. It needs to be updated too.

It appears that test /opt/features/geometry_columns/data/data_values_table_name (Requirement 23) is supposed to test for the foreign key relationships but that test is completely wrong (function name and table name are both incorrect and the test is incomprehensible) and needs to be rewritten.

[jyutzler]

PR Confirmed by the SWG today.