Add User-Agent to web hook service

app/services/web_hook_service.rb

@@ -120,6 +120,7 @@ class WebHookService
     @headers ||= begin
       {
         'Content-Type' => 'application/json',
+        'User-Agent' => "GitLab/#{Gitlab::VERSION}",
         GITLAB_EVENT_HEADER => self.class.hook_to_event(hook_name)
       }.tap do |hash|
         hash['X-Gitlab-Token'] = Gitlab::Utils.remove_line_breaks(hook.token) if hook.token.present?

changelogs/unreleased/gregmyers-webhook-useragent.yml

+---
+title: Add User-Agent to web hook service
+merge_request: 46070
+author:
+type: added

spec/services/web_hook_service_spec.rb

@@ -10,6 +10,7 @@ RSpec.describe WebHookService do
   let(:headers) do
     {
       'Content-Type' => 'application/json',
+      'User-Agent' => "GitLab/#{Gitlab::VERSION}",
       'X-Gitlab-Event' => 'Push Hook'
     }
   end