wallet: Replace "non-0" with "non-zero" in translatable error message

Transifex interprets the "-0" substring as a number in translatable
strings. Since not all translations preserve "-0," this triggers a
corresponding warning. While this warning could be disabled globally, it
is more reasonable to adjust the original string instead.

Author: hebasto

src/wallet/spend.cpp

@@ -1138,7 +1138,7 @@ static util::Result<CreatedTransactionResult> CreateTransactionInternal(
     // This can only happen if feerate is 0, and requested destinations are value of 0 (e.g. OP_RETURN)
     // and no pre-selected inputs. This will result in 0-input transaction, which is consensus-invalid anyways
     if (selection_target == 0 && !coin_control.HasSelected()) {
-        return util::Error{_("Transaction requires one destination of non-0 value, a non-0 feerate, or a pre-selected input")};
+        return util::Error{_("Transaction requires one destination of non-zero value, a non-zero feerate, or a pre-selected input")};
     }
 
     // Fetch manually selected coins

test/functional/rpc_psbt.py

@@ -999,7 +999,7 @@ def test_psbt_input_keys(psbt_input, keys):
             {'hex': '0200000001dddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddd0000000000000000000100000000000000000000000000', 'complete': True})
 
         self.log.info("Test we don't crash when making a 0-value funded transaction at 0 fee without forcing an input selection")
-        assert_raises_rpc_error(-4, "Transaction requires one destination of non-0 value, a non-0 feerate, or a pre-selected input", self.nodes[0].walletcreatefundedpsbt, [], [{"data": "deadbeef"}], 0, {"fee_rate": "0"})
+        assert_raises_rpc_error(-4, "Transaction requires one destination of non-zero value, a non-zero feerate, or a pre-selected input", self.nodes[0].walletcreatefundedpsbt, [], [{"data": "deadbeef"}], 0, {"fee_rate": "0"})
 
         self.log.info("Test descriptorprocesspsbt updates and signs a psbt with descriptors")