打包成jar, 依赖包放另外个文件夹运行, 报空指针异常

- [ ] I have searched the [issues](https://github.com/seata/seata/issues) of this repository and believe that this is not a duplicate.

### Ⅰ. Issue Description
在idea里跑是正常的, 打包成jar, 报空指针错误, 我是项目jar跟依赖jar分离运行的.
看了下源码应该是FileConfiguration的 this.getClass().getClassLoader().getResource 这行
### Ⅱ. Describe what happened

```
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'globalTransactionScanner' defined in class path resource [io/seata/spring/boot/autoconfigure/SeataAutoConfiguration.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [io.seata.spring.annotation.GlobalTransactionScanner]: Factory method 'globalTransactionScanner' threw exception; nested exception is java.lang.ExceptionInInitializerError
at org.springframework.beans.factory.support.ConstructorResolver.instantiate(ConstructorResolver.java:627)
at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:607)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1288)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1127)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:538)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:498)
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:320)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:318)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:204)
at org.springframework.context.support.PostProcessorRegistrationDelegate.registerBeanPostProcessors(PostProcessorRegistrationDelegate.java:228)
at org.springframework.context.support.AbstractApplicationContext.registerBeanPostProcessors(AbstractApplicationContext.java:707)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:531)
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:775)
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:397)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:316)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1260)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1248)
at org.ucp.plat.UcpPlatProviderApp.main(UcpPlatProviderApp.java:25)
Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [io.seata.spring.annotation.GlobalTransactionScanner]: Factory method 'globalTransactionScanner' threw exception; nested exception is java.lang.ExceptionInInitializerError
at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:185)
at org.springframework.beans.factory.support.ConstructorResolver.instantiate(ConstructorResolver.java:622)
... 18 common frames omitted
Caused by: java.lang.ExceptionInInitializerError: null
at io.seata.spring.annotation.GlobalTransactionScanner.(GlobalTransactionScanner.java:87)
at io.seata.spring.annotation.GlobalTransactionScanner.(GlobalTransactionScanner.java:143)
at io.seata.spring.boot.autoconfigure.SeataAutoConfiguration.globalTransactionScanner(SeataAutoConfiguration.java:165)
at io.seata.spring.boot.autoconfigure.SeataAutoConfiguration$$EnhancerBySpringCGLIB$$b180da3d.CGLIB$globalTransactionScanner$2()
at io.seata.spring.boot.autoconfigure.SeataAutoConfiguration$$EnhancerBySpringCGLIB$$b180da3d$$FastClassBySpringCGLIB$$347bdf97.invoke()
at org.springframework.cglib.proxy.MethodProxy.invokeSuper(MethodProxy.java:244)
at org.springframework.context.annotation.ConfigurationClassEnhancer$BeanMethodInterceptor.intercept(ConfigurationClassEnhancer.java:363)
at io.seata.spring.boot.autoconfigure.SeataAutoConfiguration$$EnhancerBySpringCGLIB$$b180da3d.globalTransactionScanner()
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:154)
... 19 common frames omitted
Caused by: java.lang.NullPointerException: null
at io.seata.config.FileConfiguration.getConfigFile(FileConfiguration.java:144)
at io.seata.config.FileConfiguration.(FileConfiguration.java:108)
at io.seata.config.ConfigurationFactory.load(ConfigurationFactory.java:63)
at io.seata.config.ConfigurationFactory.(ConfigurationFactory.java:48)
... 32 common frames omitted
```

### Ⅲ. Describe what you expected to happen

### Ⅳ. How to reproduce it (as minimally and precisely as possible)

1. xxx
2. xxx
3. xxx

### Ⅴ. Anything else we need to know?

### Ⅵ. Environment:

- JDK version : 1.8
- OS : win10
- Others:

Start with io.seata.config.FileConfiguration.getConfigFile at line 144 and trace how ConfigurationFactory.load initializes it. Reproduce the failure from UcpPlatProviderApp.main using a packaged application JAR with dependencies in a separate folder on JDK 8 and Windows 10. Done means startup no longer throws the reported NullPointerException and configuration loads in that layout.

Written by the indexing model from the issue text.