Add backup/restore tests for Memory and ScyllaDB backends (Phase 0b)#6392

ndr-ds wants to merge 4 commits into

mainlinera-io/linera-protocol:mainfrom

ndr-ds/phase-0b-memory-scylla-backup-testslinera-io/linera-protocol:ndr-ds/phase-0b-memory-scylla-backup-testsCopy head branch name to clipboard