[CONJ-309] correction of possible NPE on aurora when failover occur d…

…uring connection initialisation

src/main/java/org/mariadb/jdbc/internal/failover/impl/AuroraListener.java

@@ -191,7 +191,7 @@ public HostAddress searchByStartName(Protocol secondaryProtocol, List<HostAddres
                 //eat exception because cannot happen in this getString()
             } catch (QueryException qe) {
                 if (proxy.hasToHandleFailover(qe) && setSecondaryHostFail()) {
-                    addToBlacklist(currentProtocol.getHostAddress());
+                    addToBlacklist(secondaryProtocol.getHostAddress());
                 }
             }
         }