core: cli flag to disable grandpa (#2105)

* core: cli flag to disable grandpa

* core: fix test service configuration

* Update core/service/test/src/lib.rs

substrate/core/service/src/config.rs

@@ -70,6 +70,8 @@ pub struct Configuration<C, G: Serialize + DeserializeOwned + BuildStorage> {
 	pub default_heap_pages: Option<u64>,
 	/// Enable authoring even when offline.
 	pub force_authoring: bool,
+	/// Disable GRANDPA when running in validator mode
+	pub disable_grandpa: bool,
 }
 
 impl<C: Default, G: Serialize + DeserializeOwned + BuildStorage> Configuration<C, G> {
@@ -96,6 +98,7 @@ impl<C: Default, G: Serialize + DeserializeOwned + BuildStorage> Configuration<C
 			telemetry_endpoints: None,
 			default_heap_pages: None,
 			force_authoring: false,
+			disable_grandpa: false,
 		};
 		configuration.network.boot_nodes = configuration.chain_spec.boot_nodes().to_vec();