refactor(webmvc): Optimized the creation logic of API version request mapping handler mappings

- After you create an ApiVersionRequestMappingHandlerMapping instance, assign it to the mapping variable
- This change may help to better manage request mapping, handler mapping, and improve maintainability of your code

forgeboot-webmvc/forgeboot-webmvc-version-starter/src/main/kotlin/com/gewuyou/forgeboot/webmvc/version/config/VersionAutoConfiguration.kt

@@ -36,6 +36,7 @@ open class VersionAutoConfiguration(
         log.info("创建 API 版本请求映射处理程序映射")
         return ApiVersionRequestMappingHandlerMapping(versionProperties).also {
             it.order = Int.MIN_VALUE
+            mapping = it
         }
     }
     @PostConstruct