Move some associated types from relay_substrate_client::Chain to bp_runtime::Chain (#1087)
* move some associated types from relay_substrate_client::Chain to bp_runtime::Chain * dummy commit * Revert "dummy commit" This reverts commit 81bc64aa.
* move some associated types from relay_substrate_client::Chain to bp_runtime::Chain * dummy commit * Revert "dummy commit" This reverts commit 81bc64aa.