Revert "Introduce log_dir env variable for truemail and require it with figaro."

This reverts commit 76eed1ef08.

config/application.yml.sample

@@ -4,9 +4,6 @@
 #
 # Be sure to restart your server when you modify settings.
 #
-# Log directory for gems not using syslog
-log_dir: /home/app/current/log
-
 
 #
 # SMTP configuration (for Admin/EPP/Registrar/Registrant servers)

config/initializers/figaro.rb

@@ -5,5 +5,4 @@ Figaro.require_keys(%w[
   time_zone
   action_mailer_default_host
   action_mailer_default_from
-  log_dir
 ])

config/initializers/truemail.rb

@@ -72,6 +72,6 @@ Truemail.configure do |config|
   # stdout, write to file or both of these. Tracking event by default is :error
   # Available tracking event: :all, :unrecognized_error, :recognized_error, :error
   unless Rails.env.test?
-    config.logger = { tracking_event: :all, stdout: true, log_absolute_path: "#{ENV['log_dir']}/truemail.log" }
+    config.logger = { tracking_event: :all, stdout: true, log_absolute_path: Rails.root.join('log', 'truemail.log') }
   end
 end