### Environment

* Dubbo version: 2.7.3
* Operating System version: win 10
* Java version: 1.8

系统启动时报
Caused by: java.lang.IllegalArgumentException: Unsupported generic type false
	at org.apache.dubbo.config.ServiceConfig.setGeneric(ServiceConfig.java:1015)

这个错误只有在2.7.3的时候存在，在使用2.7.2的时候没有
completeCompoundConfigs();
        // 
        startConfigCenter();
        checkDefault();
        checkProtocol();
        checkApplication();
        // 
        if (!isOnlyInJvm()) {
            checkRegistry();
        }
        this.refresh();
        checkMetadataReport();
        if (StringUtils.isEmpty(interfaceName)) {
            throw new IllegalStateException("<dubbo:service interface=\"\" /> interface not allow null!");
        }
        if (ref instanceof GenericService) {
            interfaceClass = GenericService.class;
            if (StringUtils.isEmpty(generic)) {
                generic = Boolean.TRUE.toString();
            }
        } else {
            try {
                interfaceClass = Class.forName(interfaceName, true, Thread.currentThread()
                        .getContextClassLoader());
            } catch (ClassNotFoundException e) {
                throw new IllegalStateException(e.getMessage(), e);
            }
            checkInterfaceAndMethods(interfaceClass, methods);
            checkRef();
            generic = Boolean.FALSE.toString();