Test each benchmark case in own #[test] (#9860)

* Generate one #[test] fn per bench case.

* Update benchmark macro syntax in frame pallets.

* Explain new benchmark macro syntax in example pallet.

* support with and without a semicolon

* update pallets to use individual tests

* migrate staking too

* migrate more pallets

* fix up democracy and use individual tests

* Fix comment

* Put println message in panic

* Remove `another_set_dummy` from doc

`another_set_dummy` is not present in the benchmarking.rs (anymore).

* Update doc for benchmarks macro

* Update doc for impl_benchmark_test_suite macro

Co-authored-by: Shawn Tabrizi <shawntabrizi@gmail.com>

substrate/frame/staking/src/benchmarking.rs

@@ -887,6 +887,13 @@ benchmarks! {
 	verify {
 		assert!(!T::SortedListProvider::contains(&stash));
 	}
+
+	impl_benchmark_test_suite!(
+		Staking,
+		crate::mock::ExtBuilder::default().has_stakers(true),
+		crate::mock::Test,
+		exec_name = build_and_execute
+	);
 }
 
 #[cfg(test)]
@@ -1001,10 +1008,3 @@ mod tests {
 		});
 	}
 }
-
-impl_benchmark_test_suite!(
-	Staking,
-	crate::mock::ExtBuilder::default().has_stakers(true),
-	crate::mock::Test,
-	exec_name = build_and_execute
-);

substrate/frame/staking/src/lib.rs

@@ -272,6 +272,7 @@
 //!   validators is stored in the Session pallet's `Validators` at the end of each era.
 
 #![cfg_attr(not(feature = "std"), no_std)]
+#![recursion_limit = "256"]
 
 #[cfg(feature = "runtime-benchmarks")]
 pub mod benchmarking;