Fixes gitaly#629

Signed-off-by: Rémy Coutable <remy@rymai.me>

Signed-off-by: Rémy Coutable <remy@rymai.me>

I first attempted to extract logic from the code that normalizes DNs, but I was unsuccessful. This is a hack but it works.

Especially from the last attribute value.

Disabling some for now since this is based on `Net::LDAP::DN`.

for normalizing and parsing DNs