chore: upgrade Solidity version from 0.8.20 to 0.8.22

Upgrade all contracts to Solidity 0.8.22 for improved compiler
optimizations and language features.

Author: juliaaschmidt

contracts/src/Administrable.sol

@@ -1,5 +1,5 @@
 //SPDX-License-Identifier: BUSL-1.1
-pragma solidity 0.8.20;
+pragma solidity 0.8.22;
 
 import "./interfaces/IAdministrable.sol";
 

contracts/src/Allowlist.1.sol

@@ -1,5 +1,5 @@
 //SPDX-License-Identifier: BUSL-1.1
-pragma solidity 0.8.20;
+pragma solidity 0.8.22;
 
 import "./interfaces/IAllowlist.1.sol";
 import "./interfaces/IProtocolVersion.sol";

contracts/src/CoverageFund.1.sol

@@ -1,5 +1,5 @@
 //SPDX-License-Identifier: BUSL-1.1
-pragma solidity 0.8.20;
+pragma solidity 0.8.22;
 
 import "./interfaces/IRiver.1.sol";
 import "./interfaces/IAllowlist.1.sol";

contracts/src/ELFeeRecipient.1.sol

@@ -1,5 +1,5 @@
 //SPDX-License-Identifier: BUSL-1.1
-pragma solidity 0.8.20;
+pragma solidity 0.8.22;
 
 import "./interfaces/IRiver.1.sol";
 import "./interfaces/IELFeeRecipient.1.sol";

contracts/src/Firewall.sol

@@ -1,5 +1,5 @@
 //SPDX-License-Identifier: BUSL-1.1
-pragma solidity 0.8.20;
+pragma solidity 0.8.22;
 
 import "./interfaces/IFirewall.sol";
 import "./interfaces/IProtocolVersion.sol";

contracts/src/Initializable.sol

@@ -1,5 +1,5 @@
 //SPDX-License-Identifier: BUSL-1.1
-pragma solidity 0.8.20;
+pragma solidity 0.8.22;
 
 import "./state/shared/Version.sol";
 

contracts/src/OperatorsRegistry.1.sol

@@ -1,5 +1,5 @@
 //SPDX-License-Identifier: BUSL-1.1
-pragma solidity 0.8.20;
+pragma solidity 0.8.22;
 
 import "./interfaces/IOperatorRegistry.1.sol";
 import "./interfaces/IRiver.1.sol";

contracts/src/Oracle.1.sol

@@ -1,5 +1,5 @@
 //SPDX-License-Identifier: BUSL-1.1
-pragma solidity 0.8.20;
+pragma solidity 0.8.22;
 
 import "./interfaces/IRiver.1.sol";
 import "./interfaces/IOracle.1.sol";

contracts/src/ProtocolMetrics.1.sol

@@ -1,5 +1,5 @@
 //SPDX-License-Identifier: BUSL-1.1
-pragma solidity 0.8.20;
+pragma solidity 0.8.22;
 
 import {ISharesManagerV1} from "./interfaces/components/ISharesManager.1.sol";
 import {Initializable} from "./Initializable.sol";

contracts/src/RedeemManager.1.sol

@@ -1,5 +1,5 @@
 //SPDX-License-Identifier: BUSL-1.1
-pragma solidity 0.8.20;
+pragma solidity 0.8.22;
 
 import "./interfaces/IAllowlist.1.sol";
 import "./interfaces/IRiver.1.sol";