Fix advisory to not use object_store 0.9.1

[tillrohrmann]

Currently, our Datafusion dependency (35.0.0) relies on the object_store dependency 0.9.1 which has a security vulnerability. Unfortunately, we cannot simply bump the version since it would also require bumping Datafusion. Bumping Datafusion is currently blocked on some problems with joins (see #1673).

Technically, we shouldn't be using object_store (also not indirectly). Therefore, we should not be affected by this vulnerability.