`current_application_settings` belongs on `Gitlab::CurrentSettings`

The initializers including this were doing so at the top level, so every object
loaded after them had a `current_application_settings` method. However, if
someone had rack-attack enabled (which was loaded before these initializers), it
would try to load the API, and fail, because `Gitlab::CurrentSettings` didn't
have that method.

To fix this:

1. Don't include `Gitlab::CurrentSettings` at the top level. We do not need
   `Object.new.current_application_settings` to work.
2. Make `Gitlab::CurrentSettings` explicitly `extend self`, as we already use it
   like that in several places.
3. Change the initializers to use that new form.

1 files changed, 2 insertions, 2 deletions

diff --git a/spec/helpers/version_check_helper_spec.rb b/spec/helpers/version_check_helper_spec.rb
index 5eba03ef576..fa8cfda3b86 100644
--- a/spec/helpers/version_check_helper_spec.rb
+++ b/spec/helpers/version_check_helper_spec.rb
@@ -4,7 +4,7 @@ describe VersionCheckHelper do
   describe '#version_status_badge' do
     it 'should return nil if not dev environment and not enabled' do
       allow(Rails.env).to receive(:production?) { false }
-      allow(current_application_settings).to receive(:version_check_enabled) { false }
+      allow(helper.current_application_settings).to receive(:version_check_enabled) { false }
 
       expect(helper.version_status_badge).to be(nil)
     end
@@ -12,7 +12,7 @@ describe VersionCheckHelper do
     context 'when production and enabled' do
       before do
         allow(Rails.env).to receive(:production?) { true }
-        allow(current_application_settings).to receive(:version_check_enabled) { true }
+        allow(helper.current_application_settings).to receive(:version_check_enabled) { true }
         allow_any_instance_of(VersionCheck).to receive(:url) { 'https://version.host.com/check.svg?gitlab_info=xxx' }
 
         @image_tag = helper.version_status_badge