[pallet-revive] allow delegate calls to non-contract accounts (#7729)

This PR changes the behavior of delegate calls when the callee is not a
contract account: Instead of returning a `CodeNotFound` error, this is
allowed and the caller observes a successful call with empty output.

The change makes for example the following contract behave the same as
on EVM:

```Solidity
contract DelegateCall {
    function delegateToLibrary() external returns (bool) {
        address testAddress = 0x0000000000000000000000000000000000000000;
        (bool success, ) = testAddress.delegatecall(
            abi.encodeWithSignature("test()")
        );
        return success;
    }
}
```

Closes https://github.com/paritytech/revive/issues/235

---------

Signed-off-by: xermicus <cyrill@parity.io>
Co-authored-by: cmd[bot] <41898282+github-actions[bot]@users.noreply.github.com>