Add tests/integration/object/bucket/rw, the first slice carved from the
legacy testObjectStoreOperations. It provisions an OBC on the shared store,
writes, reads back, and deletes an object over S3, and checks the OBC stays
Bound. It runs against the shared store in both the TLS and non-TLS passes.
Drop the converted put/get and OBC-revert subtests from the legacy test;
the user quota subtest now seeds both of the objects it needs. The
remaining quota, policy, lifecycle, and dependents slices convert in later
PRs.
Signed-off-by: Joshua Hoblitt <josh@hoblitt.com>