1953 defensive testing extrinsic (#1998)

# Description

The `trigger_defensive` call has been added to the `root-testing`
pallet. The idea is to have this pallet running on `Rococo/Westend` and
use it to verify if the runtime monitoring works end-to-end.

To accomplish this, `trigger_defensive` dispatches an event when it is
called.

Closes #1953

# Checklist

- [x] My PR includes a detailed description as outlined in the
"Description" section above
- [ ] My PR follows the [labeling requirements](CONTRIBUTING.md#Process)
of this project (at minimum one label for `T`
  required)
- [ ] I have made corresponding changes to the documentation (if
applicable)
- [ ] I have added tests that prove my fix is effective or that my
feature works (if applicable)

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✄
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Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>
Co-authored-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

substrate/frame/utility/src/tests.rs

@@ -132,7 +132,7 @@ frame_support::construct_runtime!(
 		System: frame_system::{Pallet, Call, Config<T>, Storage, Event<T>},
 		Timestamp: pallet_timestamp::{Call, Inherent},
 		Balances: pallet_balances::{Pallet, Call, Storage, Config<T>, Event<T>},
-		RootTesting: pallet_root_testing::{Pallet, Call, Storage},
+		RootTesting: pallet_root_testing::{Pallet, Call, Storage,  Event<T>},
 		Council: pallet_collective::<Instance1>,
 		Utility: utility::{Pallet, Call, Event},
 		Example: example::{Pallet, Call},
@@ -187,7 +187,9 @@ impl pallet_balances::Config for Test {
 	type MaxHolds = ();
 }
 
-impl pallet_root_testing::Config for Test {}
+impl pallet_root_testing::Config for Test {
+	type RuntimeEvent = RuntimeEvent;
+}
 
 impl pallet_timestamp::Config for Test {
 	type Moment = u64;