Path's joined wrong if encoding is disabled

I am trying to join path for the router (which is using path-to-regexp).

```
const path = properUrlJoin('some-path', '/:id?/:subnav?/:step?', {
    trailingSlash: true,
    queryOptions: {
        encode: false,
    },
})
```
expected output should be
```
/some-path/:id?/:subnav?/:step?/
```
but it results to
```
/flow/:id/?/:subnav?/:step? 
```