core: fix too many nesting levels bug

The C# implementation only decrements the nesting depth once
in the parent composite condition (And, Or, or Not) and then
passes that already‐decremented value onto its subconditions
 without further decrementing inside the loop.

Close #3809

Signed-off-by: Ekaterina Pavlova <[email protected]>

pkg/core/transaction/witness_condition.go

@@ -234,7 +234,7 @@ func readArrayOfConditions(r *io.BinReader, maxDepth int) []WitnessCondition {
 	}
 	a := make([]WitnessCondition, l)
 	for i := range a {
-		a[i] = decodeBinaryCondition(r, maxDepth-1)
+		a[i] = decodeBinaryCondition(r, maxDepth)
 	}
 	if r.Err != nil {
 		return nil