fix: Move calls to env() out of UsersTableSeeder

env() calls should be made *only* from within config files.

Note that the 'owner-username' is not prepended with 'default-' because,
unlike the other two values, it should not be changed after
installation, specifically because the account should always be
looked-up by username and not ID (despite existing code that currently
does the latter).

app/Http/Controllers/ContactController.php

@@ -40,7 +40,7 @@ class ContactController extends Controller
     public function store(Request $request)
     {
         // Fetch owner account
-        $user = User::where('id', '=', 3)->first();
+        $user = User::where('username', config('unit3d.owner-username'))->first();
 
         $input = $request->all();
         Mail::to($user->email, $user->username)->send(new Contact($input));