Rename irker service to integration

Renames the project association from irker_servie to irker_integration.

app/models/integration.rb

@@ -47,6 +47,7 @@ class Integration < ApplicationRecord
     emails_on_push ewm emails_on_push external_wiki
     flowdock
     hangouts_chat
+    irker
   ].to_set.freeze
 
   def self.renamed?(name)

app/models/project.rb

@@ -171,7 +171,7 @@ class Project < ApplicationRecord
   has_one :external_wiki_integration, class_name: 'Integrations::ExternalWiki'
   has_one :flowdock_integration, class_name: 'Integrations::Flowdock'
   has_one :hangouts_chat_integration, class_name: 'Integrations::HangoutsChat'
-  has_one :irker_service, class_name: 'Integrations::Irker'
+  has_one :irker_integration, class_name: 'Integrations::Irker'
   has_one :jenkins_service, class_name: 'Integrations::Jenkins'
   has_one :jira_service, class_name: 'Integrations::Jira'
   has_one :mattermost_service, class_name: 'Integrations::Mattermost'

spec/lib/gitlab/import_export/all_models.yml

@@ -370,7 +370,7 @@ project:
 - pipelines_email_service
 - mattermost_slash_commands_service
 - slack_slash_commands_service
-- irker_service
+- irker_integration
 - packagist_service
 - pivotaltracker_service
 - prometheus_service

spec/models/project_spec.rb

@@ -51,7 +51,7 @@ RSpec.describe Project, factory_default: :keep do
     it { is_expected.to have_one(:drone_ci_integration) }
     it { is_expected.to have_one(:emails_on_push_integration) }
     it { is_expected.to have_one(:pipelines_email_service) }
-    it { is_expected.to have_one(:irker_service) }
+    it { is_expected.to have_one(:irker_integration) }
     it { is_expected.to have_one(:pivotaltracker_service) }
     it { is_expected.to have_one(:flowdock_integration) }
     it { is_expected.to have_one(:assembla_integration) }