Fix preferred_envs warning in mix.exs

Author: sabiwara

.github/workflows/ci.yml

@@ -7,6 +7,8 @@ jobs:
     # https://github.com/erlef/setup-beam/issues/161#issuecomment-1336129218
     runs-on: ubuntu-20.04
     name: OTP ${{matrix.otp}} / Elixir ${{matrix.elixir}}
+    env:
+      MIX_ENV: test
     strategy:
       matrix:
         include:

mix.exs

@@ -11,15 +11,6 @@ defmodule Aja.MixProject do
       deps: deps(),
       consolidate_protocols: Mix.env() != :test,
       aliases: aliases(),
-      preferred_cli_env: [
-        inch: :docs,
-        docs: :docs,
-        "hex.publish": :docs,
-        dialyzer: :dialyzer,
-        cover: :test,
-        "test.unit": :test,
-        "test.prop": :test
-      ],
 
       # Hex
       description:
@@ -77,6 +68,19 @@ defmodule Aja.MixProject do
     ]
   end
 
+  def cli do
+    [
+      preferred_envs: [
+        docs: :docs,
+        "hex.publish": :docs,
+        dialyzer: :dialyzer,
+        cover: :test,
+        "test.unit": :test,
+        "test.prop": :test
+      ]
+    ]
+  end
+
   defp package do
     [
       maintainers: ["sabiwara"],