fix: correct domain from pezkuwi.io to pezkuwichain.io

The pezkuwi.io domain does not exist. All references have been
updated to the correct pezkuwichain.io domain.

Fixed files:
- subxt examples (rpc.pezkuwichain.io)
- subxt lib.rs documentation
- contracts fixtures (homepage, authors email)
- CHANGELOG.md (zagros-rpc.pezkuwichain.io)

vendor/pezkuwi-subxt/subxt/examples/block_decoding_static.rs

@@ -16,7 +16,7 @@ use pezkuwi::runtime_types::sp_runtime::multiaddress::MultiAddress;
 #[tokio::main]
 async fn main() -> Result<(), Box<dyn std::error::Error>> {
 	// Create a client that subscribes to blocks of the Pezkuwi network.
-	let api = OnlineClient::<PezkuwiConfig>::from_url("wss://rpc.pezkuwi.io:443").await?;
+	let api = OnlineClient::<PezkuwiConfig>::from_url("wss://rpc.pezkuwichain.io:443").await?;
 
 	// Subscribe to all finalized blocks:
 	let mut blocks_sub = api.blocks().subscribe_finalized().await?;