Fix MIX_ENV for docs generation

Author: aj-foster

.github/workflows/main.yml

@@ -43,7 +43,7 @@ jobs:
           MIX_ENV=dev mix compile
           MIX_ENV=test mix compile
           MIX_ENV=prod mix compile
-          MIX_ENV=prod mix docs
+          MIX_ENV=dev mix docs
 
       - name: Upload Docs
         id: docs