Support asynchronous processing

[rayuuuu]

Is your feature request related to a problem? Please describe.

When generating a large number of API documentation, it can be slow

Describe the solution you'd like

Reduce generation time

Describe alternatives you've considered

I looked at the source code, and the handling of each api is synchronous. Can we adopt an asynchronous way to process it? I tried it locally, and the speed improved significantly. Document generation also worked without issues, but I'm not sure if there are any other hidden problems

// the main changes in  OpenApiResource
protected void calculatePath(Map<String, Object> restControllers, Map<RequestMappingInfo, HandlerMethod> map, Locale locale, OpenAPI openAPI) {
		TreeMap<RequestMappingInfo, HandlerMethod> methodTreeMap = new TreeMap<>(byReversedRequestMappingInfos());
		methodTreeMap.putAll(map);
		Optional<SpringWebProvider> springWebProviderOptional = springDocProviders.getSpringWebProvider();
		springWebProviderOptional.ifPresent(springWebProvider -> {
            methodTreeMap.entrySet().stream().parallel().forEach(entry -> {    // new change, asyn
//	old		for (Map.Entry<RequestMappingInfo, HandlerMethod> entry : methodTreeMap.entrySet()) {
				RequestMappingInfo requestMappingInfo = entry.getKey();
				HandlerMethod handlerMethod = entry.getValue();
				Set<String> patterns = springWebProvider.getActivePatterns(requestMappingInfo);
				if (!CollectionUtils.isEmpty(patterns)) {
					Map<String, String> regexMap = new LinkedHashMap<>();
					for (String pattern : patterns) {
						String operationPath = PathUtils.parsePath(pattern, regexMap);
						String[] produces = requestMappingInfo.getProducesCondition().getProducibleMediaTypes().stream().map(MimeType::toString).toArray(String[]::new);
						String[] consumes = requestMappingInfo.getConsumesCondition().getConsumableMediaTypes().stream().map(MimeType::toString).toArray(String[]::new);
						String[] headers = requestMappingInfo.getHeadersCondition().getExpressions().stream().map(Object::toString).toArray(String[]::new);
						String[] params = requestMappingInfo.getParamsCondition().getExpressions().stream().map(Object::toString).toArray(String[]::new);
						if ((isRestController(restControllers, handlerMethod, operationPath) || isActuatorRestController(operationPath, handlerMethod))
								&& isFilterCondition(handlerMethod, operationPath, produces, consumes, headers)) {
							Set<RequestMethod> requestMethods = requestMappingInfo.getMethodsCondition().getMethods();
							// default allowed requestmethods
							if (requestMethods.isEmpty())
								requestMethods = this.getDefaultAllowedHttpMethods();
							calculatePath(handlerMethod, operationPath, requestMethods, consumes, produces, headers, params, locale, openAPI);
						}
					}
				}
			});
		});
	}

Additional context

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