Zsh autocomplete hardcodes DAML_HOME

[samuel-williams-da]

From Tomi:

Hi. I’ve noticed that the Daml Assistance command completion script for Zsh (I guess for Bash too) does not take 
$DAML_HOME into account. It looks for the daml binary in 
IFS=$'\n' completions=($( /Users/tamaskalcza/.daml/bin/daml "${request[@]}" )) in my case.
This is obviously problematic if Daml is installed to a custom location.
I personally use a custom location, but Daml installed with Nix has the same problem.
I do think this is minor, however worth adding to a TODO list.