conftest, save_*: Port code to updated swh-scheduler API
The oldest part of the scheduler API was updated to use model classes (based on attr package) instead of dictionaries in order to improve typing.
Depends on swh-scheduler!378 (merged)
The oldest part of the scheduler API was updated to use model classes (based on attr package) instead of dictionaries in order to improve typing.
Depends on swh-scheduler!378 (merged)