Issue 10502 - Can't get fullyQualifiedName of a templated struct

https://d.puremagic.com/issues/show_bug.cgi?id=10502

Required compiler fix:
https://github.com/D-Programming-Language/dmd/pull/3339

A compiler fix that would be better to merge at the same time:
https://github.com/D-Programming-Language/dmd/pull/3338