Add map property in url params

[agilob]

Adding map property in url params to test generation of this specific case in generators as requested in #10116 (comment)

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@wing328

[kuhnroyal]

Damn, I did this yesterday but didn't open a PR cause of the 5.2.1 release :)

[kuhnroyal]

Can you copy the tests from https://github.com/kuhnroyal/openapi-generator/tree/dart-dio/query-maps

[agilob]

It's hard to distil your change and find what's dart-test change you want added and what is generated, but I think I found what was missing

[kuhnroyal]

Looks about right, just needs some formatting.

[agilob]

Is that test supposed to be failing?

[kuhnroyal]

Is that test supposed to be failing?

I think this is just a formatting failure. Can you run dart format . in the test project?

[agilob]

I removed the commits adding the dart tests. They are failing locally and I feel they are out of scope for this PR, as I only wanted to add spec changes without anything language specific. I'll let you add the tests as you want, I think I missed some changes from your PR...