Remove services from safe model attributes

This is not needed anymore. We can also delete the check for services
relation as they are going to be ignored by the importer.

changelogs/unreleased/220342-remove-services-from-import-export.yml

 ---
-title: Exclude integrations (services) from import/export
+title: Exclude integrations (services) from Project Import/Export
 merge_request: 35249
 author:
 type: changed

lib/gitlab/import_export/project/relation_factory.rb

@@ -70,10 +70,8 @@ module Gitlab
         private
 
         def invalid_relation?
-          # Do not create relation if it is:
-          #   - A service
-          #   - A legacy trigger
-          service? || legacy_trigger?
+          # Do not create relation if it is a legacy trigger
+          legacy_trigger?
         end
 
         def setup_models
@@ -137,10 +135,6 @@ module Gitlab
           end
         end
 
-        def service?
-          @relation_name == :services
-        end
-
         def legacy_trigger?
           @relation_name == :'Ci::Trigger' && @relation_hash['owner_id'].nil?
         end

spec/lib/gitlab/import_export/safe_model_attributes.yml

@@ -461,36 +461,6 @@ DeployKey:
 - public
 - can_push
 - last_used_at
-Service:
-- id
-- type
-- title
-- project_id
-- created_at
-- updated_at
-- active
-- properties
-- template
-- instance
-- alert_events
-- push_events
-- issues_events
-- commit_events
-- merge_requests_events
-- tag_push_events
-- note_events
-- pipeline_events
-- job_events
-- comment_on_event_enabled
-- comment_detail
-- category
-- default
-- wiki_page_events
-- confidential_issues_events
-- confidential_note_events
-- deployment_events
-- description
-- inherit_from_id
 ProjectHook:
 - id
 - url