Enable approval-voting-parallel by default on kusama (paritytech#6218)

The approval-voting-parallel introduced with
paritytech#4849 has been tested on
`versi` and approximately 3 weeks on parity's existing kusama nodes
paritytech/devops#3583, things worked as
expected, so enable it by default on all kusama nodes in the next
release.

The next step will be enabling by default on polkadot if no issue
arrises while running on kusama.

---------

Signed-off-by: Alexandru Gheorghe <alexandru.gheorghe@parity.io>

polkadot/node/service/src/lib.rs

@@ -759,13 +759,12 @@ pub fn new_full<
 		Some(backoff)
 	};
 
-	// Running approval voting in parallel is enabled by default on all networks except Polkadot and
-	// Kusama, unless explicitly enabled by the commandline option.
+	// Running approval voting in parallel is enabled by default on all networks except Polkadot
+	// unless explicitly enabled by the commandline option.
 	// This is meant to be temporary until we have enough confidence in the new system to enable it
 	// by default on all networks.
-	let enable_approval_voting_parallel = (!config.chain_spec.is_kusama() &&
-		!config.chain_spec.is_polkadot()) ||
-		enable_approval_voting_parallel;
+	let enable_approval_voting_parallel =
+		!config.chain_spec.is_polkadot() || enable_approval_voting_parallel;
 
 	let disable_grandpa = config.disable_grandpa;
 	let name = config.network.node_name.clone();

prdoc/pr_6218.prdoc

@@ -0,0 +1,9 @@
+title: Enable approval-voting-parallel by default on kusama
+
+doc:
+  - audience: Node Dev
+    description: |
+        Enable approval-voting-parallel by default on kusama
+crates:
+  - name: polkadot-service
+    bump: patch