Potential panic in default executor visit_register_role

[dima74]

Looks like return should be added after executor.deny(err)? Otherwise execute! will panic in case if branch with executor.deny(err) is reached

iroha/crates/iroha_executor/src/default.rs

Lines 1305 to 1309 in a90040c

	if let Err(err) = executor.host().submit(isi) {
	executor.deny(err);
	}
	execute!(executor, grant_role);