* chore: update task tests to use the tenant service
After the introduction of the tenant system we need to switch the testing frameworks
to use it instead of the old kv system
* chore: update onboarding to allow injected middleware
* refactor: migrator and introduce Store.(Create|Delete)Bucket
feat: kvmigration internal utility to create / managing kv store migrations
fix: ensure migrations applied in all test cases
* chore: update kv and migration documentation