Return type of calls returning a lambda

[alfonsogarciacaro]

This commit fixed currying when applicating lambdas to the return value of a call (see test "Aliasing a function wrapping a multi-arity function in point-free style #2045"), however it broke the plugin in Fable.SvelteStore to generate declarations, see fable-compiler/Fable.Store#9 (comment)

This happens because the uncurrying needs to use the non-filled generic type, but for things like printing the .d.ts we need the actual type with generic args filled. Ideally we should have both the actual type of the lambda arguments and the expected generics as we have for the calls, but to avoid breaking the AST for now we're going to use the generic version only when the call returns a lambda.