BABE's revert procedure (#11022)

* First rough draft for BABE revert

* Proper babe revert test

* Cleanup

* Test trivial cleanup

* Fix to make clippy happy

* Check polkadot companion

* Check cumulus companion

* Remove babe's blocks weight on revert

* Handle "empty" blockchain edge case

* Run companions

* Simplify the filter predicate

* Saturating sub is not required

* Run pipeline

* Run pipeline again...

substrate/bin/node-template/node/src/command.rs

@@ -95,7 +95,7 @@ pub fn run() -> sc_cli::Result<()> {
 			runner.async_run(|config| {
 				let PartialComponents { client, task_manager, backend, .. } =
 					service::new_partial(&config)?;
-				Ok((cmd.run(client, backend), task_manager))
+				Ok((cmd.run(client, backend, None), task_manager))
 			})
 		},
 		Some(Subcommand::Benchmark(cmd)) =>