### 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
return buf.toString();
    }
    public static boolean isGeneric(String generic) {
        return generic != null
                && !"".equals(generic)
                && (GENERIC_SERIALIZATION_DEFAULT.equalsIgnoreCase(generic)  
                || GENERIC_SERIALIZATION_NATIVE_JAVA.equalsIgnoreCase(generic) 
                || GENERIC_SERIALIZATION_BEAN.equalsIgnoreCase(generic)
                || GENERIC_SERIALIZATION_PROTOBUF.equalsIgnoreCase(generic)
                || GENERIC_RAW_RETURN.equalsIgnoreCase(generic));
    }
    public static boolean isDefaultGenericSerialization(String generic) {
        return isGeneric(generic)
                && GENERIC_SERIALIZATION_DEFAULT.equalsIgnoreCase(generic);
    }
    public static boolean isJavaGenericSerialization(String generic) {
        return isGeneric(generic)
                && GENERIC_SERIALIZATION_NATIVE_JAVA.equalsIgnoreCase(generic);
    }
    public static boolean isBeanGenericSerialization(String generic) {
        return isGeneric(generic) && GENERIC_SERIALIZATION_BEAN.equals(generic);
    }
    public static boolean isProtobufGenericSerialization(String generic) {
        return isGeneric(generic) && GENERIC_SERIALIZATION_PROTOBUF.equals(generic);
    }
    public static boolean isGenericReturnRawResult(String generic) {
        return GENERIC_RAW_RETURN.equals(generic);
    }
}