review fix: issue when using recursively defined annotation in shadow class

[surli]

Fix #1698

[surli]

The fix here consists in checking that when visiting an annotation for shadow class creation, the parent call wasn't already the visit of an annotation of the same type.
It means that in the given AliasFor annotation (see the test), if you inspect the fields, they won't have any annotation on them even if in the file definition it uses AliasFor annotation.

So, it's not perfect but it was the easiest way to propose a fix in that kind of case.

[monperrus]

OK for me, thanks @surli . Will merge it on Monday if everybody agrees.

[monperrus]

thanks @surli!