- [x] I have searched the [issues](https://github.com/apache/dubbo/issues) of this repository and believe that this is not a duplicate.
- [ ] I have checked the [FAQ](https://github.com/apache/dubbo/blob/master/FAQ.md) of this repository and believe that this is not a duplicate.

### Environment

* Dubbo version: 3.0.1
* Spring 5.3.9
* Java version: 1.8

### Steps to reproduce this issue
最近发现dubbo3.0已经发布好久了,而且也已经第三个版本了. 遂考虑将本地的dubbo-2.7.8升级到3.0.1, 可再项目启动的时候报
`Caused by: java.lang.IllegalArgumentException: Could not resolve placeholder 'dubbo.application' in value "${dubbo.application}"
	at org.springframework.util.PropertyPlaceholderHelper.parseStringValue(PropertyPlaceholderHelper.java:174)
	at org.springframework.util.PropertyPlaceholderHelper.replacePlaceholders(PropertyPlaceholderHelper.java:126)
	at org.springframework.core.env.AbstractPropertyResolver.doResolvePlaceholders(AbstractPropertyResolver.java:236)
	at org.springframework.core.env.AbstractPropertyResolver.resolveRequiredPlaceholders(AbstractPropertyResolver.java:210)
	at org.springframework.core.env.AbstractEnvironment.resolveRequiredPlaceholders(AbstractEnvironment.java:572)
	at org.apache.dubbo.config.spring.schema.DubboBeanDefinitionParser.resolvePlaceholders(DubboBeanDefinitionParser.java:519)
	at org.apache.dubbo.config.spring.schema.DubboBeanDefinitionParser.parse(DubboBeanDefinitionParser.java:101)
	at org.apache.dubbo.config.spring.schema.DubboBeanDefinitionParser.parse(DubboBeanDefinitionParser.java:505)
	at org.springframework.beans.factory.xml.NamespaceHandlerSupport.parse(NamespaceHandlerSupport.java:74)
	at org.apache.dubbo.config.spring.schema.DubboNamespaceHandler.parse(DubboNamespaceHandler.java:90)
	at org.springframework.beans.factory.xml.BeanDefinitionParserDelegate.parseCustomElement(BeanDefinitionParserDelegate.java:1435)
	at org.springframework.beans.factory.xml.BeanDefinitionParserDelegate.parseCustomElement(BeanDefinitionParserDelegate.java:1419)
	at org.springframework.beans.factory.xml.DefaultBeanDefinitionDocumentReader.parseBeanDefinitions(DefaultBeanDefinitionDocumentReader.java:172)
	at org.springframework.beans.factory.xml.DefaultBeanDefinitionDocumentReader.doRegisterBeanDefinitions(DefaultBeanDefinitionDocumentReader.java:142)
	at org.springframework.beans.factory.xml.DefaultBeanDefinitionDocumentReader.registerBeanDefinitions(DefaultBeanDefinitionDocumentReader.java:94)
	at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.registerBeanDefinitions(XmlBeanDefinitionReader.java:508)
	at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.doLoadBeanDefinitions(XmlBeanDefinitionReader.java:392)`
将dubbo降到2.7.8又能正常启动, 有谁碰到这个问题没? 可以排除的问题:
1:key值拼写错误
2:本地自定义spring-*.xml中有多套PropertySources被初始化

Pls. provide [GitHub address] to reproduce this issue.

### Expected Result

What do you expected from the above steps？

### Actual Result

What actually happens?

If there is an exception, please attach the exception trace:

```
Just put your stack trace here!
```

private static void parseMethods(String id, NodeList nodeList, RootBeanDefinition beanDefinition,
                                     ParserContext parserContext) {
        if (nodeList == null) {
            return;
        }
        ManagedList methods = null;
        for (int i = 0; i < nodeList.getLength(); i++) {
            if (!(nodeList.item(i) instanceof Element)) {
                continue;
            }
            Element element = (Element) nodeList.item(i);
            if ("method".equals(element.getNodeName()) || "method".equals(element.getLocalName())) {
                String methodName = resolveAttribute(element, "name", parserContext);
                if (StringUtils.isEmpty(methodName)) {
                    throw new IllegalStateException("<dubbo:method> name attribute == null");
                }
                if (methods == null) {
                    methods = new ManagedList();
                }
                RootBeanDefinition methodBeanDefinition = parse(element,
                        parserContext, MethodConfig.class, false);
                String beanName = id + "." + methodName;
                
                
                if (!hasPropertyValue(methodBeanDefinition, "id")) {
                    addPropertyValue(methodBeanDefinition, "id", beanName);
                }
                BeanDefinitionHolder methodBeanDefinitionHolder = new BeanDefinitionHolder(
                        methodBeanDefinition, beanName);
                methods.add(methodBeanDefinitionHolder);