Fix our custom test task

[solnic]

So, we have this silly mistake that I just discovered, it causes this:

➜  sentry-elixir (solnic/fix-custom-test-task) mix help                                                                                                                                                         ✱
** (FunctionClauseError) no function clause matching in anonymous fn/1 in Mix.Tasks.Help.load_aliases/0    
    
    The following arguments were given to anonymous fn/1 in Mix.Tasks.Help.load_aliases/0:
    
        # 1
        [test: ["sentry.package_source_code", "test"]]
    
    (mix 1.17.2) lib/mix/tasks/help.ex:135: anonymous fn/1 in Mix.Tasks.Help.load_aliases/0
    (elixir 1.17.2) lib/enum.ex:1703: Enum."-map/2-lists^map/1-1-"/2
    (elixir 1.17.2) lib/map.ex:262: Map.new_from_enum/2
    (mix 1.17.2) lib/mix/tasks/help.ex:49: Mix.Tasks.Help.run/1
    (mix 1.17.2) lib/mix/task.ex:495: anonymous fn/3 in Mix.Task.run_task/5
    (mix 1.17.2) lib/mix/cli.ex:96: Mix.CLI.run_task/2
    /usr/local/bin/mix:2: (file)

...however, running mix test just works, but it doesn't run the alias, because defining the alias is most likely crashing silently.

I reckon it's something worth fixing in Mix itself.

[whatyouhide]

Yes we can probably give a much better error in Mix. Feel free to give that a try and I'll help if ya want 🙃

[solnic]

Yes we can probably give a much better error in Mix. Feel free to give that a try and I'll help if ya want 🙃

@whatyouhide I was going to suggest that I could give this a shot! will do then, thanks :)