Aio-geojson-nsw-rfs-incidents

* Bump aio_geojson_client to 0.21.
* Removed Python 3.8 support.
* Code quality improvements.

* Bumped version of upstream aio_geojson_client library to 0.20.
* Improved JSON parsing error handling, especially when not using Python's built-in JSON parsing library.
* Code quality improvements.
* Added Python 3.12 support.
* Removed Python 3.7 support.
* Bumped library versions: black, flake8, isort.
* Migrated to pytest.

* Added Python 3.11 support.
* Removed deprecated asynctest dependency.
* Bumped version of upstream aio_geojson_client library to 0.18.
* Bumped library versions: black.

* No functional changes.
* Added Python 3.10 support.
* Removed Python 3.6 support.
* Bumped version of upstream aio_geojson_client library to 0.16.
* Bumped library versions: black, flake8, isort.
* Migrated to github actions.

* Set aiohttp to a release 3.7.4 or later (thanks fabaff).
* Add license tag (thanks fabaff).
* Added Python 3.9 support.
* Bump aio_geojson_client to v0.14.
* General code improvements.

* Bumped version of upstream GeoJSON library.
* Fixes extraction of polygons from a feed (polygon without hole only).