[feat] bc: rename crate durs-blockchain -> durs-bc

.gitlab-ci.yml

Cargo.lock

lib/core/core/Cargo.toml

lib/core/core/src/commands/dbex.rs

lib/core/core/src/lib.rs

lib/modules/blockchain/blockchain/Cargo.toml

...ules/blockchain/blockchain/tests/apply_blocks_cautious.rs

lib/modules/blockchain/blockchain/tests/common.rs

lib/modules/blockchain/blockchain/tests/revert_blocks.rs