These two lists are updated by workloads as assets are discovered and
deployed. As these are defined as class attributes in the base Workload
class, the same two list instances are shared between all classes. This
results in subsequent workloads re-deploying assets from the previous
workloads, and may lead to mismatches with deployable_assets, which is
overwritten on per-workload basis.
Make these into instance attriutes to prevent these issues.