Fix expected hashmap key order in joy-test.janet

[veqqq]

The keys are in the wrong order, causing the test to fail. It's fairly brittle, as a random change to Janet internals could change the output order again - but hashmaps don't care about order, so this is just kicking the bucket down the road.

[sarna]

I've been thinking - maybe it'd be better to use an object that serializes predictably, ie all objects must have at most one key? For example, {:array [{:name "value"} {:number 1}]} would always end up as {"array": [{"name": "value"}, {"number": 1}]}.