The function `Request.check` did not work properly due to
`Container.contains_all` performing the check with the operands swapped.
Fix the call and improve the body of `ObjectSet.issubset`.
Also improve the error message, highlighting the missing objects.
Optimize the `run` function to skip objects that have just been
serialized when deserializing objects for outgoing requests. For
example, previously if a schedule had for a savepoint:
```yaml
incoming: ["/binary"]
outgoing: ["/binary"]
```
then the `Savepoint.run` function would have first serialized the object
into storage and then deserialized it right after, instead with the new
function the object is only serialized.
Fix the invalidation logic in both `InMemoryStorageProvider` and
`Sqlite3StorageProvider`, as it did not account for propagating the
invalidation to both children objects and parent objects.
Giacomo Vercesi