Failing tests for keyword list -> tuple conversion

[bcardarella]

@NduatiK this is necessary for the stylesheet Elixir map to json conversion task.

Some background, we were previously parsing named arguments into a single keyword list. However, in SwiftUI named arguments are individual arguments not a combination of a few into a single argument. For example this modifiers:

fooBar(10, a: 1, b: 2, 5)

has arity of 4 but our parser actually converts this into arity of 3:

{:fooBar, [], [10, [a: 1, b: 2], 5]}

Instead we want to represent named arguments are tuple pairs:

{:fooBar, [], [10, {:a, 1}, {:b, 2}, 5]}

I've updated the tests to reflect this change and just need the parser updated.

[NduatiK]

Hey, @bcardarella, the change makes sense, I've made some modifications to the tests and addressed the failures.

PS. These pending PRs are related to the JSON changes:

1. Change stylesheet output to JSON live_view_native_stylesheet#87
2. Prepare SwiftUI parser for outputing stylesheet as a map #1458
3. Prepare Jetpack parser for outputing stylesheet as a map liveview-client-jetpack#473

2 and 3 are ready for review, but I think they depend on 1.