Simplify listers Model constructor

the default implementation of SQLAlchemy's declarative API should
work just fine.

swh/lister/gitlab/models.py

@@ -15,14 +15,3 @@ class GitLabModel(ModelBase):
 
     uid = Column(String, primary_key=True)
     instance = Column(String, index=True)
-
-    def __init__(self, uid=None, indexable=None, name=None,
-                 full_name=None, html_url=None, origin_url=None,
-                 origin_type=None, description=None, task_id=None,
-                 origin_id=None, instance=None):
-        super().__init__(uid=uid, name=name,
-                         full_name=full_name, html_url=html_url,
-                         origin_url=origin_url, origin_type=origin_type,
-                         description=description, task_id=task_id,
-                         origin_id=origin_id)
-        self.instance = instance