The RPC docs are now enforced to specify the json type of the args and results at compile time. However, some help texts contain the type twice. (E.g. https://github.com/bitcoin/bitcoin/pull/17809#discussion_r386295217 ). The duplicate type in the description should be removed.

Duplicates can be found with this command:

```sh
git grep --extended-regexp  'RPC.*(ARR|OBJ).*json (array|object)' src/rpc/ src/wallet/rpc*
```

#### Useful skills:

Basic understanding of how to compile and run Bitcoin Core.

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if (!RemoveWallet(wallet)) {
        throw JSONRPCError(RPC_MISC_ERROR, "Requested wallet already unloaded");
    }
    UnloadWallet(std::move(wallet));
    return NullUniValue;
}
static UniValue listunspent(const JSONRPCRequest& request)
{
    std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
    const CWallet* const pwallet = wallet.get();
    if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
        return NullUniValue;
    }
    RPCHelpMan{
                "listunspent",
                "\nReturns array of unspent transaction outputs\n"
                "with between minconf and maxconf (inclusive) confirmations.\n"
                "Optionally filter to only include txouts paid to specified addresses.\n",
                {
                    {"minconf", RPCArg::Type::NUM,  "1", "The minimum confirmations to filter"},
                    {"maxconf", RPCArg::Type::NUM,  "9999999", "The maximum confirmations to filter"},
                    {"addresses", RPCArg::Type::ARR,  "empty array", "A json array of bitcoin addresses to filter",
                        {
                            {"address", RPCArg::Type::STR, RPCArg::Optional::OMITTED, "bitcoin address"},
                        },
                    },
                    {"include_unsafe", RPCArg::Type::BOOL,  "true", "Include outputs that are not safe to spend\n"
            "                  See description of \"safe\" attribute below."},