Fix Optional handling for default value in state handlebar helper (#29)

Fix Optional handling for default value in state handlebar helper

## References

#25 

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Author: dirkbolte

src/main/java/org/wiremock/extensions/state/extensions/StateHandlerbarHelper.java

@@ -61,14 +61,14 @@ public Object apply(Object o, Options options) {
                 .orElseGet(() ->
                     Optional
                     .ofNullable(defaultValue)
-                        .orElse(handleError(String.format("No state for context %s, property %s found", contextName, property)))
+                        .orElseGet(() -> handleError(String.format("No state for context %s, property %s found", contextName, property)))
                 );
         } else {
             return getList(contextName, list)
                 .orElseGet(() ->
                 Optional
                     .ofNullable(defaultValue)
-                    .orElse(handleError(String.format("No state for context %s, list %s found", contextName, list)))
+                    .orElseGet(() -> handleError(String.format("No state for context %s, list %s found", contextName, list)))
             );
 
         }