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.

}
        int i = Integer.parseInt(value);
        getNumbers().put(key, i);
        return i;
    }
    public short getParameter(String key, short defaultValue) {
        Number n = getNumbers().get(key);
        if (n != null) {
            return n.shortValue();
        }
        String value = getParameter(key);
        if (StringUtils.isEmpty(value)) {
            return defaultValue;
        }
        short s = Short.parseShort(value);
        getNumbers().put(key, s);
        return s;
    }
    public byte getParameter(String key, byte defaultValue) {
        Number n = getNumbers().get(key);
        if (n != null) {
            return n.byteValue();
        }
        String value = getParameter(key);
        if (StringUtils.isEmpty(value)) {
            return defaultValue;
        }
        byte b = Byte.parseByte(value);
        getNumbers().put(key, b);
        return b;