fixup! feat: Add version log

---

Added copyright to a file and Fixed the following clippy warnings:

---

warning: this import is redundant
 --> log/build.rs:1:1
  |
1 | use built;
  | ^^^^^^^^^^ help: remove it entirely
  |
  = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#single_component_path_imports
  = note: `#[warn(clippy::single_component_path_imports)]` on by default

---

warning: this import is redundant
 --> dispatcher/src/main.rs:4:1
  |
4 | use log;
  | ^^^^^^^^ help: remove it entirely
  |
  = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#single_component_path_imports
  = note: `#[warn(clippy::single_component_path_imports)]` on by default

offchain/dispatcher/src/main.rs

@@ -1,8 +1,6 @@
 // (c) Cartesi and individual authors (see AUTHORS)
 // SPDX-License-Identifier: Apache-2.0 (see LICENSE)
 
-use log;
-
 // NOTE: doesn't support History upgradability.
 // NOTE: doesn't support changing epoch_duration in the middle of things.
 #[tokio::main]

offchain/log/build.rs

@@ -1,4 +1,5 @@
-use built;
+// (c) Cartesi and individual authors (see AUTHORS)
+// SPDX-License-Identifier: Apache-2.0 (see LICENSE)
 
 pub(crate) fn main() {
     built::write_built_file()