fix build warning when compiling the app

[Adzz]

should fix this:

[AndrewDryga]

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[coveralls]

Coverage remained the same at 100.0% when pulling faded34d81054d5d7cf682ab0cd2faf2f2f2c4df on nested-tech:fix-compilation-warnings into c92fd2eb440bc53a29f2a0097a3be687dc85ad6e on Nebo15:master.

[AndrewDryga]

Hey @Adzz. The test won't work after your fix because we are using doctests and they are sensitive for additional spaces. I'm pretty sure there is magical fix for this (like using some sigil for doc comment), but not sure which one to use. If you can find a way to fix this - it would be awesome :).

[Adzz]

Ah good point!

@AndrewDryga I can see two simple solutions, which do you prefer?

1. Don't split the output over two lines
2. something like this:

   @error_message """
   can not resolve key MY_TEST_ENV value via adapter Elixir.Confex.Adapters.SystemEnvironment
   """
   # ... more code
   """
     iex> :ok = System.delete_env("MY_TEST_ENV")
     ...> Application.put_env(:myapp, :test_var, {:system, :integer, "MY_TEST_ENV"})
     ...> #{__MODULE__}.fetch_env!(:myapp, :test_var)
     ** (ArgumentError) can't fetch value for key `:test_var` of application `:myapp`, #{@error_message}
   """

The other option is to sack of doctests, and use normal tests, but I imagine that's a no!

Sigils wont work. ~S""" means the string wont let you use escape codes, which means we can't escape a new line, which means we have to have one long line anyway.

[AndrewDryga]

Let's leave it in on long line then