Harmonize listers parameters and add test to check mandatory ones

Ensure that all lister classes have the same set of mandatory parameters
in their constructors, notably: scheduler, url, instance and credentials.

Add a new test checking listers classes have mandatory parameters declared
in their constructors. The purpose is to avoid deployment issues on staging
or production environment as celery tasks can fail to be executed if mandatory
parameters are not handled by listers.

Reated to swh/infra/sysadm-environment#5030.

swh/lister/cpan/lister.py

@@ -1,4 +1,4 @@
-# Copyright (C) 2022  The Software Heritage developers
+# Copyright (C) 2022-2023  The Software Heritage developers
 # See the AUTHORS file at the top-level directory of this distribution
 # License: GNU General Public License version 3, or any later version
 # See top-level LICENSE file for more information
@@ -80,6 +80,8 @@ class CpanLister(StatelessLister[CpanListerPage]):
     def __init__(
         self,
         scheduler: SchedulerInterface,
+        url: str = API_BASE_URL,
+        instance: str = INSTANCE,
         credentials: Optional[CredentialsType] = None,
         max_origins_per_page: Optional[int] = None,
         max_pages: Optional[int] = None,
@@ -88,8 +90,8 @@ class CpanLister(StatelessLister[CpanListerPage]):
         super().__init__(
             scheduler=scheduler,
             credentials=credentials,
-            instance=self.INSTANCE,
-            url=self.API_BASE_URL,
+            instance=instance,
+            url=url,
             max_origins_per_page=max_origins_per_page,
             max_pages=max_pages,
             enable_origins=enable_origins,