Fix OIDCConfig Admin

E.g. the scopes were not editable

feudal/backend/admin.py

@@ -146,7 +146,7 @@ flush_idp.short_description = 'Delete users and vos related to the selected oidc
 class OIDCConfigAdmin(ModelAdmin):
     list_display = ('name', 'client_id', 'issuer_uri', 'enabled')
     fields = ('name', 'client_id', 'client_secret', 'issuer_uri', 'enabled', 'scopes', 'userinfo_field_groups', 'userinfo_field_entitlements')
-    readonly_fields = ('issuer_uri')
+    readonly_fields = ('issuer_uri',)
     actions = (flush_idp,)
 
 site.register(Group, GroupAdmin)