Maintenance patch and fixes

[zyadsober1]

* Smaller JSON dump output using separators

If specified, separators should be an (item_separator, key_separator) tuple. The default is (', ', ': ') if indent is None and (',', ': ') otherwise. To get the most compact JSON representation, you should specify (',', ':') to eliminate whitespace.

https://docs.python.org/2/library/json.html#json.dump
https://docs.python.org/3/library/json.html#json.dump

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* Changed the test's URLs from https://swapi.co to https://swapi.dev

Change note from the devs: https://swapi.dev/about

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* Removed warning about PyYAML load not specifying a loader

Use of PyYAML's yaml.load function without specifying the Loader=... parameter, has been deprecated. In PyYAML version 5.1+, you will get a warning, but the function will still work.

https://github.com/yaml/pyyaml/wiki/PyYAML-yaml.load(input)-Deprecation