Fixed OutOfMemory error if initializing fails (#10924)

Signed-off-by: Gerhard Riegler <gerhard.riegler@gmail.com>

bundles/org.openhab.binding.gardena/src/main/java/org/openhab/binding/gardena/internal/GardenaSmartImpl.java

@@ -133,6 +133,7 @@ public class GardenaSmartImpl implements GardenaSmart, GardenaSmartWebSocketList
             startWebsockets();
             initialized = true;
         } catch (Exception ex) {
+            dispose();
             throw new GardenaException(ex.getMessage(), ex);
         }
     }