Tag memory safe assembly blocks (#5193)

contracts/governance/Governor.sol

@@ -769,7 +769,7 @@ abstract contract Governor is Context, ERC165, EIP712, Nonces, IGovernor, IERC72
 
         // Extract what would be the `#proposer=0x` marker beginning the suffix
         bytes12 marker;
-        assembly {
+        assembly ("memory-safe") {
             // - Start of the string contents in memory = description + 32
             // - First character of the marker = len - 52
             //   - Length of "#proposer=0x0000000000000000000000000000000000000000" = 52

contracts/metatx/ERC2771Forwarder.sol

@@ -286,7 +286,7 @@ contract ERC2771Forwarder is EIP712, Nonces {
 
             uint256 gasLeft;
 
-            assembly {
+            assembly ("memory-safe") {
                 success := call(reqGas, to, value, add(data, 0x20), mload(data), 0, 0)
                 gasLeft := gas()
             }

contracts/utils/introspection/ERC165Checker.sol

@@ -113,7 +113,7 @@ library ERC165Checker {
         bool success;
         uint256 returnSize;
         uint256 returnValue;
-        assembly {
+        assembly ("memory-safe") {
             success := staticcall(30000, account, add(encodedParams, 0x20), mload(encodedParams), 0x00, 0x20)
             returnSize := returndatasize()
             returnValue := mload(0x00)