Allow setting `usage_ping_enabled` in `gitlab.rb`

This setting is passed through to the Rails app, and defaults to true. Setting
it to false:

1. Disables the usage ping.
2. Prevents the usage ping from being enabled through the admin panel. It can
   only be enabled by either removing the line from `gitlab.rb` and configuring
   through the admin panel, or setting it to true in `gitlab.rb`.

CHANGELOG.md

@@ -5,6 +5,7 @@ omnibus-gitlab repository.
 9.2.0
+- Allow setting `usage_ping_enabled` in `gitlab.rb`
 - Update mysql client to 5.5.55
 - Add a build env variable ALTERNATIVE_SOURCES f0cab0c6
 - Create reconfigure log dir explicitly (Anastas Dancha) 9654cfe3

files/gitlab-cookbooks/gitlab/attributes/default.rb

@@ -141,6 +141,7 @@ default['gitlab']['gitlab-rails']['registry_api_url'] = nil
 default['gitlab']['gitlab-rails']['registry_key_path'] = nil
 default['gitlab']['gitlab-rails']['registry_path'] = nil
 default['gitlab']['gitlab-rails']['registry_issuer'] = "omnibus-gitlab-issuer"
+default['gitlab']['gitlab-rails']['usage_ping_enabled'] = nil
 # Defaults set in libraries/gitlab_rails.rb
 default['gitlab']['gitlab-rails']['repositories_storages'] = {}

files/gitlab-cookbooks/gitlab/templates/default/gitlab.yml.erb

@@ -85,6 +85,8 @@ production: &base
     # The default is 'tmp/repositories' relative to the root of the Rails app.
     repository_downloads_path: <%= @gitlab_repository_downloads_path %>
+    usage_ping_enabled: <%= @usage_ping_enabled %>
+
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