Merge #6058: fix: reset rounds to 0 when tx fee is not 0

0365b06fab fix: reset rounds to 0 when tx fee is not 0 (UdjinM6)

Pull request description:

  ## Issue being fixed or feature implemented
  > a coinjoin send with say 10x 1 + 0.001 denom -> 10 denom, and this doesn’t reset rounds to 0

  reported by @PastaPastaPasta 👍

  ## What was done?
  only real coinjoin tx can be a 0 fee tx with denoms, use that fact to avoid the edge case described above

  ## How Has This Been Tested?
  reproduced the issue

  ## Breaking Changes
  n/a

  ## Checklist:
  - [x] I have performed a self-review of my own code
  - [ ] I have commented my code, particularly in hard-to-understand areas
  - [ ] I have added or updated relevant unit/integration/functional/e2e tests
  - [ ] I have made corresponding changes to the documentation
  - [x] I have assigned this pull request to a milestone _(for repository code-owners and collaborators only)_

ACKs for top commit:
  PastaPastaPasta:
    ACK 0365b06fab

Tree-SHA512: b72ac5c01cc77c81945c3ae00b80fbdc4884acf3cfadc3fbcf4b78ff5655cce3b2ece4885478e5bf7476d351411df88b967d2baa3925155cffdc6054dd3bb502

src/wallet/wallet.cpp

@@ -1413,6 +1413,13 @@ int CWallet::GetRealOutpointCoinJoinRounds(const COutPoint& outpoint, int nRound
         }
     }
 
+    // make sure we spent all of it with 0 fee, reset to 0 rounds otherwise
+    if (wtx->GetDebit(ISMINE_SPENDABLE) != wtx->GetCredit(ISMINE_SPENDABLE)) {
+        *nRoundsRef = 0;
+        WalletCJLogPrint((*this), "%s UPDATED   %-70s %3d\n", __func__, outpoint.ToStringShort(), *nRoundsRef);
+        return *nRoundsRef;
+    }
+
     int nShortest = -10; // an initial value, should be no way to get this by calculations
     bool fDenomFound = false;
     // only denoms here so let's look up