[Bug] jdk21+dubbo3.3.6 start npe

### Pre-check

- [x] I am sure that all the content I provide is in English.

### Search before asking

- [x] I had searched in the [issues](https://github.com/apache/dubbo/issues?q=is%3Aissue) and found no similar issues.

### Apache Dubbo Component

Java SDK (apache/dubbo)

### Dubbo Version

Dubbo 3.3.6，OpenJDK 21，SpringBoot 3.3.1，Maven Project

### Steps to reproduce this issue

org.apache.dubbo
dubbo-spring-boot-starter
3.3.6


org.apache.dubbo
dubbo-nacos-spring-boot-starter
3.3.6

### What you expected to happen

`java.lang.IllegalStateException: Failed to create adaptive instance: java.lang.IllegalStateException: Can't create adaptive extension interface org.apache.dubbo.metrics.report.MetricsReporterFactory, cause: Cannot invoke "java.lang.reflect.AccessibleObject.setAccessible(boolean)" because "ao" is null
at org.apache.dubbo.common.extension.ExtensionLoader.getAdaptiveExtension(ExtensionLoader.java:739)
at org.apache.dubbo.config.deploy.DefaultApplicationDeployer.initMetricsReporter(DefaultApplicationDeployer.java:406)
at org.apache.dubbo.config.deploy.DefaultApplicationDeployer.initialize(DefaultApplicationDeployer.java:230)
at org.apache.dubbo.config.deploy.DefaultModuleDeployer.prepare(DefaultModuleDeployer.java:665)
at org.apache.dubbo.config.spring.context.DubboConfigApplicationListener.initDubboConfigBeans(DubboConfigApplicationListener.java:85)
at org.apache.dubbo.config.spring.context.DubboConfigApplicationListener.init(DubboConfigApplicationListener.java:68)
at org.apache.dubbo.config.spring.context.DubboConfigApplicationListener.onApplicationEvent(DubboConfigApplicationListener.java:59)
at org.apache.dubbo.config.spring.context.DubboConfigApplicationListener.onApplicationEvent(DubboConfigApplicationListener.java:38)
at org.springframework.context.event.SimpleApplicationEventMulticaster.doInvokeListener(SimpleApplicationEventMulticaster.java:185)
at org.springframework.context.event.SimpleApplicationEventMulticaster.invokeListener(SimpleApplicationEventMulticaster.java:178)
at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:156)
at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:138)
at org.springframework.context.support.AbstractApplicationContext.registerListeners(AbstractApplicationContext.java:925)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:621)
at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:146)
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:754)
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:456)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:335)
at com.yxing.lmb.pthub.start.PthubApplication.main(PthubApplication.java:26)
Caused by: java.lang.IllegalStateException: Can't create adaptive extension interface org.apache.dubbo.metrics.report.MetricsReporterFactory, cause: Cannot invoke "java.lang.reflect.AccessibleObject.setAccessible(boolean)" because "ao" is null
at org.apache.dubbo.common.extension.ExtensionLoader.createAdaptiveExtension(ExtensionLoader.java:1445)
at org.apache.dubbo.common.extension.ExtensionLoader.getAdaptiveExtension(ExtensionLoader.java:735)
... 18 more`

### Anything else

_No response_

### Do you have a (mini) reproduction demo?

- [ ] Yes, I have a minimal reproduction demo to help resolve this issue more effectively!

### Are you willing to submit a pull request to fix on your own?

- [ ] Yes I am willing to submit a pull request on my own!

### Code of Conduct

- [x] I agree to follow this project's [Code of Conduct](https://www.apache.org/foundation/policies/conduct)