[staking miner]: add CLI tests + fix --version (#5024)

* staking miner: add CLI tests

* cargo fmt

* fix bad merge

* Update utils/staking-miner/Cargo.toml

Co-authored-by: Kian Paimani <5588131+kianenigma@users.noreply.github.com>

* grumbles: derive PartialEq only for tests

* make test `--version` a integration tests

Co-authored-by: Kian Paimani <5588131+kianenigma@users.noreply.github.com>

polkadot/utils/staking-miner/tests/cli.rs

@@ -0,0 +1,12 @@
+use assert_cmd::{cargo::cargo_bin, Command};
+
+#[test]
+fn cli_version_works() {
+	let crate_name = env!("CARGO_PKG_NAME");
+	let output = Command::new(cargo_bin(crate_name)).arg("--version").output().unwrap();
+
+	assert!(output.status.success(), "command returned with non-success exit code");
+	let version = String::from_utf8_lossy(&output.stdout).trim().to_owned();
+
+	assert_eq!(version, format!("{} {}", crate_name, env!("CARGO_PKG_VERSION")));
+}