TSAbstractMethodDefinition is not used for abstract constructors

[azz]

What version of TypeScript are you using?

n/a

What version of typescript-eslint-parser are you using?

master (post 2.1.0)

What code were you trying to parse?

abstract class Foo {
  abstract constructor();
}

What did you expect to happen?

AST for the constructor to have type TSAbstractMethodDefinition.

What happened?

AST for the constructor has type MethodDefinition.