Add support for solc 0.8.21

[pcaversaccio]

https://github.com/ethereum/solidity/releases/tag/v0.8.21

[pcaversaccio]

Cc: @roynalnaruto @mattsse

[pcaversaccio]

For anyone coming here, you can now access events from other contracts (this will help with Foundry tests)!

[mattsse]

fyi @Evalir need to build and publish new svm-rs

[Evalir]

on it chief

[pcaversaccio]

For anyone interested, I also added support for dapptools already dapphub/dapptools#987

[pcaversaccio]

For anyone interested in the new event-selecting feature, there is an unfortunate ICE in Solidity due to NatSpec parsing: ethereum/solidity#14430. For anyone who wants to use that feature and compiles with a mode that requires NatSpec parsing need to wait for solc 0.8.22. Example of a contract which will not compile unfortunately:

// SPDX-License-Identifier: MIT
pragma solidity 0.8.21;

contract X {
    event E();
}

contract C {
    function g() public {
        emit X.E();
    }
}