[BUG] when running jupinx `--files` the index_toc page is not included

@AakashGfude I have tried to figure this one out but failed so far. 

If you run

```bash
jupinx -cws --files=source/rst/arma.rst
```
the page build (along with associated index files -- except for the `index_toc` page? Do you know why this is the case. Sphinx seems to think `index_toc` is not a dependent / linked file. This makes local previews difficult. 