You cannot eval completion scripts for multiple binaries.

When you try to eval two different completion scripts for two different binaries only the last one is working correctly.

e.g.
Evalutuating the folowing code will result in completion working properly only for the binary2
```
eval "$(binary1 --completion-script-zsh)"
eval "$(binary2 --completion-script-zsh)"
```

The issue seems to be caused by running `compinit` again, which resets completion module and removes previously added autocompletion scripts.

I propose to remove calls to `compinit` and `bashcompinit` and leave this responsibility to the user.