fix nullability hack for new swagger version

Author: SirCotare

src/main/java/it/aboutbits/springboot/toolbox/swagger/customization/default_not_null/NullableCustomizer.java

@@ -18,9 +18,12 @@ public void customise(OpenAPI openApi) {
                     if (((Schema<?>) schema).getProperties() != null) {
                         var requiredProperties = new ArrayList<String>();
                         ((Schema<?>) schema).getProperties().forEach((propertyName, property) -> {
-                            if (property.getNullable() == null || !property.getNullable()) {
+                            if (property.getTitle() == null || !property.getTitle().equals("NULLABLE")) {
                                 requiredProperties.add(propertyName);
                             }
+                            if (property.getTitle() != null && property.getTitle().equals("NULLABLE")) {
+                                property.setTitle(null);
+                            }
                         });
                         schema.setRequired(requiredProperties);
                     }

src/main/java/it/aboutbits/springboot/toolbox/swagger/customization/default_not_null/NullablePropertyCustomizer.java

@@ -31,7 +31,7 @@ public Schema<?> customize(Schema property, AnnotatedType annotatedType) {
 
         if (annotatedType.getCtxAnnotations() != null && Arrays.stream(annotatedType.getCtxAnnotations())
                 .anyMatch(a -> "Nullable".equals(a.annotationType().getSimpleName()))) {
-            property.setNullable(true);
+            property.setTitle("NULLABLE");
         }
 
         return property;