Merge #18341: doc: Replace remaining literal BTC with CURRENCY_UNIT.

7df0cf7 Replace remaining literals BTC with CURRENCY_UNIT (Daniel Kraft)

Pull request description:

  This replaces one remaining instance of the literal `"BTC"` string with the `CURRENCY_UNIT` constant, as is done in most of the codebase already.

  After this change, no instance of literal `"BTC"` remains anywhere in the RPC help texts.

ACKs for top commit:
  MarcoFalke:
    ACK 7df0cf7
  laanwj:
    ACK 7df0cf7

Tree-SHA512: 7f7d52b366e084c93a7d6a3c45b1bbfc4f4f50bca6956594077e6d46295977c8cc18499232878869869c73a8ab9a1c41245029ae7425a87cec2ccb0cb52eea13

Author: laanwj

src/validation.cpp

@@ -974,7 +974,7 @@ bool MemPoolAccept::Finalize(ATMPArgs& args, Workspace& ws)
     // Remove conflicting transactions from the mempool
     for (CTxMemPool::txiter it : allConflicting)
     {
-        LogPrint(BCLog::MEMPOOL, "replacing tx %s with %s for %s BTC additional fees, %d delta bytes\n",
+        LogPrint(BCLog::MEMPOOL, "replacing tx %s with %s for %s additional fees, %d delta bytes\n",
                 it->GetTx().GetHash().ToString(),
                 hash.ToString(),
                 FormatMoney(nModifiedFees - nConflictingFees),

src/wallet/rpcwallet.cpp

@@ -3361,7 +3361,7 @@ static UniValue bumpfee(const JSONRPCRequest& request)
             "                         the dust threshold."},
                             {"fee_rate", RPCArg::Type::NUM, /* default */ "fallback to 'confTarget'", "FeeRate (NOT total fee) to pay, in " + CURRENCY_UNIT + " per kB\n"
             "                         Specify a fee rate instead of relying on the built-in fee estimator.\n"
-            "                         Must be at least 0.0001 BTC per kB higher than the current transaction fee rate.\n"},
+                                     "Must be at least 0.0001 " + CURRENCY_UNIT + " per kB higher than the current transaction fee rate.\n"},
                             {"replaceable", RPCArg::Type::BOOL, /* default */ "true", "Whether the new transaction should still be\n"
             "                         marked bip-125 replaceable. If true, the sequence numbers in the transaction will\n"
             "                         be left unchanged from the original. If false, any input sequence numbers in the\n"