Remove 5_backend.rb as it's not adding value

.rubocop_todo/layout/line_length.yml

@@ -630,7 +630,6 @@ Layout/LineLength:
     - 'config/application.rb'
     - 'config/initializers/01_secret_token.rb'
     - 'config/initializers/1_settings.rb'
-    - 'config/initializers/5_backend.rb'
     - 'config/initializers/7_prometheus_metrics.rb'
     - 'config/initializers/8_devise.rb'
     - 'config/initializers/active_record_force_reconnects.rb'

config/initializers/5_backend.rb

-# frozen_string_literal: true
-
-unless Rails.env.test?
-  required_version = Gitlab::VersionInfo.parse(Gitlab::Shell.version_required)
-  current_version = Gitlab::VersionInfo.parse(Gitlab::Shell.version)
-
-  unless current_version.valid? && required_version <= current_version
-    warn "WARNING: This version of GitLab depends on gitlab-shell #{required_version}, but you're running #{current_version}. Please update gitlab-shell."
-  end
-end