
### Environment

* Dubbo version: dubbo-2.6.4
* Operating System version: windows 10
* Java version: JDK1.8

When run the testcase(com.alibaba.dubbo.config.AbstractInterfaceConfigTest#checkApplication1) in windows environment,It will be wrong. 

So It should add scene judgement in windows environment(org.apache.dubbo.common.utils.ConfigUtils#loadProperties(java.lang.String, boolean, boolean),Line 220).

```java
if (fileName.startsWith("/")) {
````
change to
```java
if (fileName.startsWith("/")||fileName.matches("^[A-z]:\\\\\\S+$")) {
````
the testcase (com.alibaba.dubbo.config.AbstractInterfaceConfigTest#checkApplication1) will go well.





return loadProperties(fileName, false, false);
    }
    public static Properties loadProperties(String fileName, boolean allowMultiFile) {
        return loadProperties(fileName, allowMultiFile, false);
    }
    /**
     * Load properties file to {@link Properties} from class path.
     *
     * @param fileName       properties file name. for example: <code>dubbo.properties</code>, <code>METE-INF/conf/foo.properties</code>
     * @param allowMultiFile if <code>false</code>, throw {@link IllegalStateException} when found multi file on the class path.
     * @param optional       is optional. if <code>false</code>, log warn when properties config file not found!s
     * @return loaded {@link Properties} content. <ul>
     * <li>return empty Properties if no file found.
     * <li>merge multi properties file if found multi file
     * </ul>
     * @throws IllegalStateException not allow multi-file, but multi-file exsit on class path.
     */
    public static Properties loadProperties(String fileName, boolean allowMultiFile, boolean optional) {
        Properties properties = new Properties();
        if (fileName.startsWith("/")) {
            try {
                FileInputStream input = new FileInputStream(fileName);
                try {
                    properties.load(input);
                } finally {
                    input.close();
                }
            } catch (Throwable e) {
                logger.warn("Failed to load " + fileName + " file from " + fileName + "(ignore this file): " + e.getMessage(), e);
            }