lower version, for example 2.6.8
```properties
dubbo.provider.version=1.0
```

2.7.6 failed to recognize the provider url with 'default.version=1.0' key,  it only takes 'version.1.0' into consideration.

String address = "127.0.0.1";
        URL url = UrlUtils.parseURL(address, null);
        assertEquals(localAddress + ":9090", url.getAddress());
        assertEquals(9090, url.getPort());
        assertEquals("dubbo", url.getProtocol());
        assertNull(url.getUsername());
        assertNull(url.getPassword());
        assertNull(url.getPath());
    }
    @Test
    public void testParseFromParameter() {
        String address = "127.0.0.1";
        Map<String, String> parameters = new HashMap<String, String>();
        parameters.put("username", "root");
        parameters.put("password", "alibaba");
        parameters.put("port", "10000");
        parameters.put("protocol", "dubbo");
        parameters.put("path", "dubbo.test.api");
        parameters.put("aaa", "bbb");
        parameters.put("ccc", "ddd");
        URL url = UrlUtils.parseURL(address, parameters);
        assertEquals(localAddress + ":10000", url.getAddress());
        assertEquals("root", url.getUsername());
        assertEquals("alibaba", url.getPassword());
        assertEquals(10000, url.getPort());
        assertEquals("dubbo", url.getProtocol());
        assertEquals("dubbo.test.api", url.getPath());
        assertEquals("bbb", url.getParameter("aaa"));
        assertEquals("ddd", url.getParameter("ccc"));
    }