Add more database checks

[ScriptRaccoon]

• Automatically test that all of the categories mentioned below have all properties decided. This is to ensure a good database quality. In particular, when a PR adds a new property, that property needs to be decided for at least these categories.

[
	"0",
	"1",
	"2",
	"Ab",
	"Grp",
	"N",
	"R-Mod",
	"CRing",
	"Ring",
	"Set",
	"Set*",
	"Top",
	"Top*",
	"Vect",
	"walking_morphism"
]

• Refactor the test script
• Add JSDocs to all functions in the test script
• Improve the contribution guidelines: better explanation of the tests
• Add a workflow file to run the update script, which includes the test script, in the ephemeral runner environment. For now this only runs with a manual trigger, since I want to test this first. In the future, every PR will run this automatically.

Remark: if these checks turn out to be too strict, we can iterate. For example, we might introduce a threshold of unknown (category, property)-pairs.

PS: This is how the output looks like.