Avoid calling out to the client to get a sandbox controller and instead
setup the list of controllers on initialization. This fixes a test
failure which does not set the client.
Signed-off-by: Derek McGowan <derek@mcg.dev>
Before snapshotter per runtime, CRI only supports a global snapshotter.
So a snapshot can be uniquely identified by `snapshot_key`. With snapshotter
per runtime enabled, there may be multiple snapshotters used by CRI. So only
(snapshotter_id, snapshot_key) can uniquely identify a snapshot.
Also extends CRI/store/snapshot/Store to support multiple snapshotters.
Signed-off-by: Jiang Liu <gerry@linux.alibaba.com>