contracts-bedrock: update versions

packages/contracts-bedrock/contracts/libraries/Bytes.sol

 // SPDX-License-Identifier: MIT
-pragma solidity 0.8.15;
+pragma solidity ^0.8.0;
 
 /**
  * @title Bytes

packages/contracts-bedrock/contracts/libraries/Encoding.sol

 // SPDX-License-Identifier: MIT
-pragma solidity 0.8.15;
+pragma solidity ^0.8.0;
 
 import { Hashing } from "./Hashing.sol";
 import { RLPWriter } from "./rlp/RLPWriter.sol";

packages/contracts-bedrock/contracts/libraries/Hashing.sol

 // SPDX-License-Identifier: MIT
-pragma solidity 0.8.15;
+pragma solidity ^0.8.0;
 
 import { Encoding } from "./Encoding.sol";
 

packages/contracts-bedrock/contracts/libraries/Predeploys.sol

 // SPDX-License-Identifier: MIT
-pragma solidity 0.8.15;
+pragma solidity ^0.8.0;
 
 /**
  * @title Predeploys

packages/contracts-bedrock/contracts/libraries/rlp/RLPReader.sol

 // SPDX-License-Identifier: MIT
-pragma solidity 0.8.15;
+pragma solidity ^0.8.0;
 
 /**
  * @custom:attribution https://github.com/hamdiallam/Solidity-RLP

packages/contracts-bedrock/contracts/libraries/rlp/RLPWriter.sol

 // SPDX-License-Identifier: MIT
-pragma solidity 0.8.15;
+pragma solidity ^0.8.0;
 
 /**
  * @custom:attribution https://github.com/bakaoh/solidity-rlp-encode

packages/contracts-bedrock/contracts/libraries/trie/MerkleTrie.sol

 // SPDX-License-Identifier: MIT
-pragma solidity 0.8.15;
+pragma solidity ^0.8.0;
 
 import { Bytes } from "../Bytes.sol";
 import { RLPReader } from "../rlp/RLPReader.sol";

packages/contracts-bedrock/contracts/libraries/trie/SecureMerkleTrie.sol

 // SPDX-License-Identifier: MIT
-pragma solidity 0.8.15;
+pragma solidity ^0.8.0;
 
 /* Library Imports */
 import { MerkleTrie } from "./MerkleTrie.sol";

packages/contracts-bedrock/contracts/universal/CrossDomainMessenger.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.15;
+pragma solidity 0.8.15;
 
 import {
     OwnableUpgradeable

packages/contracts-bedrock/contracts/universal/OptimismMintableERC20.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.15;
+pragma solidity 0.8.15;
 
 import { ERC20 } from "@openzeppelin/contracts/token/ERC20/ERC20.sol";
 import "./SupportedInterfaces.sol";

packages/contracts-bedrock/contracts/universal/OptimismMintableERC20Factory.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.15;
+pragma solidity 0.8.15;
 
 /* Contract Imports */
 import { OptimismMintableERC20 } from "../universal/OptimismMintableERC20.sol";

packages/contracts-bedrock/contracts/universal/Proxy.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.15;
+pragma solidity 0.8.15;
 
 /**
  * @title Proxy

packages/contracts-bedrock/contracts/universal/ProxyAdmin.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.15;
+pragma solidity 0.8.15;
 
 import { Owned } from "@rari-capital/solmate/src/auth/Owned.sol";
 import { Proxy } from "./Proxy.sol";

packages/contracts-bedrock/contracts/universal/StandardBridge.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.15;
+pragma solidity 0.8.15;
 
 import { IERC20 } from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
 import { ERC165Checker } from "@openzeppelin/contracts/utils/introspection/ERC165Checker.sol";

packages/contracts-bedrock/contracts/universal/SupportedInterfaces.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.15;
+pragma solidity ^0.8.0;
 
 // Import this here to make it available just by importing this file
 import { IERC165 } from "@openzeppelin/contracts/utils/introspection/IERC165.sol";

packages/contracts-bedrock/contracts/vendor/AddressAliasHelper.sol

@@ -16,7 +16,7 @@
  * limitations under the License.
  */
 
-pragma solidity ^0.8.7;
+pragma solidity ^0.8.0;
 
 library AddressAliasHelper {
     uint160 constant offset = uint160(0x1111000000000000000000000000000000001111);