The `generate` RPC method:
- was introduced in 2010
- is now only used for testing
- reaches across multiple components (wallet, mining)

I propose we remove the wallet `generate` RPC method and update all tests to use the `generatetoaddress` RPC method. We can do this non-invasively in the test framework by adding a `generate` method to `TestNode` so that the individual tests do not need to be updated. We could also add a `generate` alias to the `generatetoaddress` RPC method.

Doing this removes a wallet->server dependency and simplifies the wallet->server interface (#10973).

I'm opening this issue before implementing in case anyone has objections.
std::vector<CPubKey> pubkeys;
    for (unsigned int i = 0; i < keys_or_addrs.size(); ++i) {
        if (IsHex(keys_or_addrs[i].get_str()) && (keys_or_addrs[i].get_str().length() == 66 || keys_or_addrs[i].get_str().length() == 130)) {
            pubkeys.push_back(HexToPubKey(keys_or_addrs[i].get_str()));
        } else {
            pubkeys.push_back(AddrToPubKey(pwallet, keys_or_addrs[i].get_str()));
        }
    }
    OutputType output_type = pwallet->m_default_address_type;
    if (!request.params[3].isNull()) {
        if (!ParseOutputType(request.params[3].get_str(), output_type)) {
            throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, strprintf("Unknown address type '%s'", request.params[3].get_str()));
        }
    }
    
    CScript inner = CreateMultisigRedeemscript(required, pubkeys);
    CTxDestination dest = AddAndGetDestinationForScript(*pwallet, inner, output_type);
    pwallet->SetAddressBook(dest, label, "send");
    UniValue result(UniValue::VOBJ);
    result.pushKV("address", EncodeDestination(dest));
    result.pushKV("redeemScript", HexStr(inner.begin(), inner.end()));
    return result;
}
class Witnessifier : public boost::static_visitor<bool>
{
public:
    CWallet * const pwallet;
    CTxDestination result;
    bool already_witness;
    explicit Witnessifier(CWallet *_pwallet) : pwallet(_pwallet), already_witness(false) {}