justl-exec-recipe-in-dir should prompt for args when needed

[MicahElliott]

According to README:

Alternatively if you want to just execute a recipe quickly, call: M-x justl-exec-recipe-in-dir

But I don't see this working for recipes with args. The completing-read kindly prompts for which recipe to select, but then does not prompt for arg(s). So the outcome is like:

error: Recipe `browse-foo` got 0 arguments but takes 1
usage:
    just browse-foo SOMEARG

[psibi]

Thanks for the bug report! I have some functions to see if a recipe accepts arguments, so I believe this would be easy to fix.

Want to give an attempt at fixing this ?