Rename constant to what bridge relayers expect (#237)

### Description
<!-- Describe what change this PR is implementing -->

### Types of Changes
<!--- What types of changes does your code introduce? -->
- [x] Bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Dependency upgrade (A change in substrate or any 3rd party crate
version)

### Migrations and Hooks
<!--- Check the following box with an x if the following applies: -->
- [ ] This change requires a runtime migration.
- [ ] Modifies `on_initialize`
- [ ] Modifies `on_finalize`

### Checklist
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requiring PR review -->
- [x] Change has been tested locally.
- [ ] Change adds / updates tests.
- [ ] Changelog doc updated.

pallets/chainbridge/src/lib.rs

@@ -142,7 +142,7 @@ pub mod pallet {
 		/// This must be unique and must not collide with existing IDs within a set of bridged
 		/// chains.
 		#[pallet::constant]
-		type ChainId: Get<ChainId>;
+		type ChainIdentity: Get<ChainId>;
 
 		#[pallet::constant]
 		type ProposalLifetime: Get<<Self as frame_system::Config>::BlockNumber>;
@@ -482,7 +482,7 @@ pub mod pallet {
 		/// Whitelist a chain ID for transfer
 		pub fn whitelist(id: ChainId) -> DispatchResult {
 			// Cannot whitelist this chain
-			ensure!(id != T::ChainId::get(), Error::<T>::InvalidChainId);
+			ensure!(id != T::ChainIdentity::get(), Error::<T>::InvalidChainId);
 			// Cannot whitelist with an existing entry
 			ensure!(!Self::chain_whitelisted(id), Error::<T>::ChainAlreadyWhitelisted);
 			<ChainNonces<T>>::insert(id, 0);

pallets/chainbridge/src/mock.rs

@@ -79,7 +79,7 @@ impl crate::pallet::Config for Test {
 	type RuntimeEvent = RuntimeEvent;
 	type AdminOrigin = frame_system::EnsureRoot<Self::AccountId>;
 	type Proposal = RuntimeCall;
-	type ChainId = TestChainId;
+	type ChainIdentity = TestChainId;
 	type ProposalLifetime = ProposalLifetime;
 	type BridgeAccountId = BridgeAccountId;
 }

pallets/erc20/src/mock.rs

@@ -77,7 +77,7 @@ impl bridge::Config for Test {
     type Event = Event;
     type AdminOrigin = frame_system::EnsureRoot<Self::AccountId>;
     type Proposal = Call;
-    type ChainId = TestChainId;
+    type ChainIdentity = TestChainId;
     type ProposalLifetime = ProposalLifetime;
 }
 

runtime/cere-dev/src/lib.rs

@@ -1235,7 +1235,7 @@ impl pallet_chainbridge::Config for Runtime {
 	type RuntimeEvent = RuntimeEvent;
 	type AdminOrigin = frame_system::EnsureRoot<Self::AccountId>;
 	type Proposal = RuntimeCall;
-	type ChainId = ChainId;
+	type ChainIdentity = ChainId;
 	type ProposalLifetime = ProposalLifetime;
 	type BridgeAccountId = BridgeAccountId;
 }

runtime/cere/src/lib.rs

@@ -1240,7 +1240,7 @@ impl pallet_chainbridge::Config for Runtime {
 	type RuntimeEvent = RuntimeEvent;
 	type AdminOrigin = frame_system::EnsureRoot<Self::AccountId>;
 	type Proposal = RuntimeCall;
-	type ChainId = ChainId;
+	type ChainIdentity = ChainId;
 	type ProposalLifetime = ProposalLifetime;
 	type BridgeAccountId = BridgeAccountId;
 }