The type checker doesn't distinguish an object from its class

[echebbi]

Bug description

We can assign a class to an object of this class.

Expected behavior

The type checker complains about an illegal assignment.

How to reproduce

Steps to reproduce the behavior:

1. Import the helloworld example project
2. Write the following code:

   open class HelloWorld {
   
      @main
      def void main() {
          HelloWorld world := helloworld::HelloWorld;
          world.log();
      }
   
   }

3. No error (correct code is HelloWorld world := helloworld::HelloWorld.create();)

Additional context

• ALE version: master @ d6e5429