Update dAppStaking precompile page to reflect V3 (#598)

* Update to reflect V3

* Update staking.md

---------

Co-authored-by: Ivan Andrisek <ivan@Ivans-MBP.fritz.box>

Author: andabak

docs/build/EVM/precompiles/staking.md

@@ -1,5 +1,6 @@
-# DApp Staking
+# dApp Staking
 
-The dApp Staking Precompile allows EVM smart contracts to access `pallet-dapps-staking` functionality.
+The dApp Staking Precompile allows EVM smart contracts to access `pallet-dapp-staking` functionality.
+
+For more information see `precompiles/dapps-staking-v3` in the [`Astar` repository](https://github.com/AstarNetwork/Astar/).
 
-For more information see `precompiles/dapps-staking/DappsStaking.sol` in the [`Astar` repository](https://github.com/AstarNetwork/Astar/).