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.

if (defaultValue <= 0) {
            throw new IllegalArgumentException("defaultValue <= 0");
        }
        long value = getMethodParameter(method, key, defaultValue);
        return value <= 0 ? defaultValue : value;
    }
    public int getMethodPositiveParameter(String method, String key, int defaultValue) {
        if (defaultValue <= 0) {
            throw new IllegalArgumentException("defaultValue <= 0");
        }
        int value = getMethodParameter(method, key, defaultValue);
        return value <= 0 ? defaultValue : value;
    }
    public short getMethodPositiveParameter(String method, String key, short defaultValue) {
        if (defaultValue <= 0) {
            throw new IllegalArgumentException("defaultValue <= 0");
        }
        short value = getMethodParameter(method, key, defaultValue);
        return value <= 0 ? defaultValue : value;
    }
    public byte getMethodPositiveParameter(String method, String key, byte defaultValue) {
        if (defaultValue <= 0) {
            throw new IllegalArgumentException("defaultValue <= 0");
        }
        byte value = getMethodParameter(method, key, defaultValue);
        return value <= 0 ? defaultValue : value;
    }
    public char getMethodParameter(String method, String key, char defaultValue) {
        String value = getMethodParameter(method, key);
        return StringUtils.isEmpty(value) ? defaultValue : value.charAt(0);