collator selection config optim (#730)

* lower min candidates to 3

* allow supermajority of tech comm to take special collator selection actions

* fix clippy

runtimes/eden/src/pallets_consensus.rs

@@ -16,9 +16,11 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-use crate::{constants, Aura, Balances, CollatorSelection, Runtime, RuntimeEvent, Session};
+use crate::{
+	constants, pallets_governance::EnsureRootOrMoreThanHalfOfTechComm, Aura, Balances, CollatorSelection, Runtime,
+	RuntimeEvent, Session,
+};
 use frame_support::{parameter_types, PalletId};
-use frame_system::EnsureRoot;
 use primitives::{AccountId, AuraId};
 use sp_runtime::impl_opaque_keys;
 use sp_std::prelude::*;
@@ -72,17 +74,14 @@ impl cumulus_pallet_aura_ext::Config for Runtime {}
 parameter_types! {
 	pub const PotId: PalletId = PalletId(*b"PotStake");
 	pub const MaxCandidates: u32 = 1000;
-	pub const MinCandidates: u32 = 5;
+	pub const MinCandidates: u32 = 3;
 	pub const MaxInvulnerables: u32 = 50;
 }
 
-// We allow root only to execute privileged collator selection operations.
-pub type CollatorSelectionUpdateOrigin = EnsureRoot<AccountId>;
-
 impl pallet_collator_selection::Config for Runtime {
 	type RuntimeEvent = RuntimeEvent;
 	type Currency = Balances;
-	type UpdateOrigin = CollatorSelectionUpdateOrigin;
+	type UpdateOrigin = EnsureRootOrMoreThanHalfOfTechComm;
 	type PotId = PotId;
 	type MaxCandidates = MaxCandidates;
 	type MinCandidates = MinCandidates;