add owner to SovaL1Block contract and make setBitcoinBlockData onlyOwner (#50)

Author: PowVT

src/SovaL1Block.sol

@@ -1,6 +1,8 @@
 // SPDX-License-Identifier: MIT
 pragma solidity 0.8.15;
 
+import "@solady/auth/Ownable.sol";
+
 import "./interfaces/ISovaL1Block.sol";
 
 /**
@@ -13,23 +15,24 @@ import "./interfaces/ISovaL1Block.sol";
  * SovaL1Block provides information about the state of the Bitcoin chain.
  * Values stored in this contract are used by validators to verify block execution.
  * The primary values used here are the Bitcoin block height and trailing block hash.
- *
- * Values within this contract are updated prior to Sova block execution via a system
- * tx and can only be set by the system account.
  */
-contract SovaL1Block is ISovaL1Block {
+contract SovaL1Block is ISovaL1Block, Ownable {
     uint64 private currentBlockHeight;
     bytes32 private blockHashSixBlocksBack;
     uint256 private lastUpdatedBlock;
 
     address private constant SYSTEM_ACCOUNT_ADDRESS = 0xDeaDDEaDDeAdDeAdDEAdDEaddeAddEAdDEAd0001;
 
+    constructor() Ownable() {
+        _initializeOwner(msg.sender);
+    }
+
     function version() external pure virtual returns (string memory) {
         return "0.1.0-beta.1";
     }
 
     function setBitcoinBlockData(uint64 _blockHeight, bytes32 _blockHash) external {
-        require(msg.sender == SYSTEM_ACCOUNT_ADDRESS, "SovaL1Block: only the system account can set block data");
+        require(msg.sender == owner(), "SovaL1Block: only the chain admin can set block data");
 
         currentBlockHeight = _blockHeight;
         blockHashSixBlocksBack = _blockHash;