Don't autocomplete already supplied arguments

There's two files in current working directory:
- [f] a.png
- [f] b.png

When writting command

```
rm [f\]\ a.png [f\]\ b.png
```

I can resort to autocompletions to write command faster.

So instead of writing whole name I can press `[` and then `→`, however when writing second filename it again suggests [f]\ a.png, which is already to be removed. I have to resort to `Tab` then writing `b` and pressing `Tab` again which could be avoided if fish didn't autocomplete filenames that were already supplied.

**EDIT**: Same with