SI-8350 SI-8387 tweak handling of new trees

Adds two tweaks to the handling of `q"new ..."` trees:

1. Makes `q"$f(...$argss)"` not match `q"new Foo(x)"` as function with arguments 
2. Makes `q"new Foo"` and `q"new Foo()"` match one another

review @xeno-by @retronym