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:

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{
    return{{RPCResult::Type::NUM, "confirmations", "The number of confirmations for the transaction. Negative confirmations means the\n"
               "transaction conflicted that many blocks ago."},
           {RPCResult::Type::BOOL, "generated", "Only present if transaction only input is a coinbase one."},
           {RPCResult::Type::BOOL, "trusted", "Only present if we consider transaction to be trusted and so safe to spend from."},
           {RPCResult::Type::STR_HEX, "blockhash", "The block hash containing the transaction."},
           {RPCResult::Type::NUM, "blockheight", "The block height containing the transaction."},
           {RPCResult::Type::NUM, "blockindex", "The index of the transaction in the block that includes it."},
           {RPCResult::Type::NUM_TIME, "blocktime", "The block time expressed in " + UNIX_EPOCH_TIME + "."},
           {RPCResult::Type::STR_HEX, "txid", "The transaction id."},
           {RPCResult::Type::ARR, "walletconflicts", "Conflicting transaction ids.",
           {
               {RPCResult::Type::STR_HEX, "txid", "The transaction id."},
           }},
           {RPCResult::Type::NUM_TIME, "time", "The transaction time expressed in " + UNIX_EPOCH_TIME + "."},
           {RPCResult::Type::NUM_TIME, "timereceived", "The time received expressed in " + UNIX_EPOCH_TIME + "."},
           {RPCResult::Type::STR, "comment", "If a comment is associated with the transaction, only present if not empty."},
           {RPCResult::Type::STR, "bip125-replaceable", "(\"yes|no|unknown\") Whether this transaction could be replaced due to BIP125 (replace-by-fee);\n"
               "may be unknown for unconfirmed transactions not in the mempool"}};
}
UniValue listtransactions(const JSONRPCRequest& request)