Disable Sidekiq arguments logging by default

Conflicts:
	config/initializers/4_sidekiq.rb

CHANGELOG

 v 7.5.1
   - Add missing timestamps to 'members' table
+v 7.5.2
+  - Don't log Sidekiq arguments by default
+
 v 7.5.0
   - API: Add support for Hipchat (Kevin Houdebert)
   - Add time zone configuration on gitlab.yml (Sullivan Senechal)

config/initializers/4_sidekiq.rb

@@ -14,7 +14,8 @@ Sidekiq.configure_server do |config|
   }
   config.server_middleware do |chain|
-    chain.add Gitlab::SidekiqMiddleware::ArgumentsLogger
+    chain.add Gitlab::SidekiqMiddleware::ArgumentsLogger if ENV['SIDEKIQ_LOG_ARGUMENTS']
+    chain.add Gitlab::SidekiqMiddleware::MemoryKiller if ENV['SIDEKIQ_MAX_RSS']
   end
 end

doc/development/README.md

@@ -4,3 +4,4 @@
 - [Shell commands](shell_commands.md) in the GitLab codebase
 - [Rake tasks](rake_tasks.md) for development
 - [CI setup](ci_setup.md) for testing GitLab
+- [Sidekiq debugging](sidekiq_debugging.md)

doc/sidekiq_debugging.md

+# Sidekiq debugging
+
+## Log arguments to Sidekiq jobs
+
+If you want to see what arguments are being passed to Sidekiq jobs you can set
+the SIDEKIQ_LOG_ARGUMENTS environment variable.
+
+```
+SIDEKIQ_LOG_ARGUMENTS=1 bundle exec foreman start
+```
+
+It is not recommend to enable this setting in production because some Sidekiq
+jobs (such as sending a password reset email) take secret arguments (for
+example the password reset token).