Change assert(is_err()) to assert_noop to check state consistency on errors (#8587)

* Change is_err() asserts in tests to assert_noop to check state consistency

fixes #8545

* Update frame/transaction-payment/src/lib.rs

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

* Update frame/contracts/src/exec.rs

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

* Update frame/democracy/src/benchmarking.rs

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

* Update frame/transaction-payment/src/lib.rs

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

* Don't assert no-changing state.

see: https://github.com/paritytech/substrate/pull/8587#issuecomment-817137906

* fix expected error

* Fix non-extrinsic-call asserts

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

substrate/frame/contracts/src/exec.rs

@@ -937,7 +937,7 @@ mod tests {
 	use super::*;
 	use crate::{
 		gas::GasMeter, tests::{ExtBuilder, Test, Event as MetaEvent},
-		storage::Storage,
+		storage::{Storage, ContractAbsentError},
 		tests::{
 			ALICE, BOB, CHARLIE,
 			test_utils::{place_contract, set_balance, get_balance},
@@ -945,6 +945,7 @@ mod tests {
 		exec::ExportedFunction::*,
 		Error, Weight, CurrentSchedule,
 	};
+	use frame_support::assert_noop;
 	use sp_runtime::DispatchError;
 	use assert_matches::assert_matches;
 	use std::{cell::RefCell, collections::HashMap, rc::Rc};
@@ -1571,7 +1572,10 @@ mod tests {
 			);
 
 			// Check that the account has not been created.
-			assert!(Storage::<Test>::code_hash(&instantiated_contract_address).is_err());
+			assert_noop!(
+				Storage::<Test>::code_hash(&instantiated_contract_address),
+				ContractAbsentError,
+			);
 			assert!(events().is_empty());
 		});
 	}