Uncurried needs to default to true for ReScript 11

[cknitt]

In ReScript 11, "uncurried" is true by default (i.e., if not set explicitly in rescript.json).
However, it seems the VSCode plugin still assumes that the default is false.

To test: Create a new project using npm create rescript-app@next with the "Basic" template and add "let f = () => ()" to Demo.res.

Observe CodeLens / tool tips showing the function type as (. unit) => unit.

(tested with the latest prerelease version 1.29.5)