* fix(automap): fix naming conflicts for PostgreSQLProvider
Automaping classes and relationships from database schema throws an error if a
column name is the same as a relationship name (see
https://docs-sqlalchemy.readthedocs.io/ko/latest/orm/extensions/automap.html#handling-simple-naming-conflicts).
* renaming function name_for_scalar_relationship -> _name_for_scalar_relationship
* test: test that PostgreSQL provider can handle naming conflicts
Re-use data file from https://github.com/geopython/pygeoapi/pull/1185, and make
to new and empty tables that create naming conflicts when queried.
* Change test function post_collection_items -> get_collection_items
* fix path to table
Mathieu Tachon