Replace system config Index for Nonce (#14290)

* replace Index by Nonce

* replace Index by Nonce

* replace Index by Nonce

* replace Index by Nonce

* replace Index by Nonce

* wip

* remove index in lieu of nonce

* wip

* remove accountnonce in lieu of nonce

* add minor improvement

* rebase and merge conflicts

substrate/frame/examples/basic/src/tests.rs

@@ -51,7 +51,7 @@ impl frame_system::Config for Test {
 	type BlockLength = ();
 	type DbWeight = ();
 	type RuntimeOrigin = RuntimeOrigin;
-	type Index = u64;
+	type Nonce = u64;
 	type Hash = H256;
 	type RuntimeCall = RuntimeCall;
 	type Hashing = BlakeTwo256;

substrate/frame/examples/default-config/src/lib.rs

@@ -137,7 +137,7 @@ pub mod tests {
 
 		// all of this is coming from `frame_system::config_preludes::TestDefaultConfig`.
 
-		// type Index = u32;
+		// type Nonce = u32;
 		// type BlockNumber = u32;
 		// type Header =
 		// sp_runtime::generic::Header<frame_system::pallet_prelude::BlockNumberFor<Self>,

substrate/frame/examples/dev-mode/src/tests.rs

@@ -45,7 +45,7 @@ impl frame_system::Config for Test {
 	type BlockLength = ();
 	type DbWeight = ();
 	type RuntimeOrigin = RuntimeOrigin;
-	type Index = u64;
+	type Nonce = u64;
 	type Hash = H256;
 	type RuntimeCall = RuntimeCall;
 	type Hashing = BlakeTwo256;

substrate/frame/examples/offchain-worker/src/tests.rs

@@ -53,7 +53,7 @@ impl frame_system::Config for Test {
 	type DbWeight = ();
 	type RuntimeOrigin = RuntimeOrigin;
 	type RuntimeCall = RuntimeCall;
-	type Index = u64;
+	type Nonce = u64;
 	type Hash = H256;
 	type Hashing = BlakeTwo256;
 	type AccountId = sp_core::sr25519::Public;