Adjustments after changing null-annotations for updating properties (#12221)

Signed-off-by: Jan N. Klug <github@klug.nrw>

bundles/org.openhab.binding.hpprinter/src/main/java/org/openhab/binding/hpprinter/internal/HPPrinterHandler.java

@@ -155,7 +155,7 @@ public class HPPrinterHandler extends BaseThingHandler {
     }
 
     @Override
-    protected void updateProperties(final Map<String, String> properties) {
+    protected void updateProperties(final @Nullable Map<String, String> properties) {
         super.updateProperties(properties);
     }