Fix name collision between generic and non-generic forward declarations

[fourls]

SonarDelphi currently crashes when parsing multiple forward declarations with the same name. This usually occurs when a non-generic type and a generic type share a name and are both forward declared, such as the below:

type
  TFoo = class;
  TFoo<T> = class;

  TFoo = class(TObject)
  // ...
  end;

  TFoo<T> = class(TObject)
  // ...
  end;

This PR modifies the code that identifies forward declarations to take into account the number of generic parameters of a declaration. This resolves the crash and correctly matches a full declaration to its forward declaration.