Fix pipeline fixture seeder

What does this MR do?

This MR does the following things

• Fix broken pipeline fixture seeder db/fixtures/development/14_pipelines.rb

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Conforms to the code review guidelines
  • Has been reviewed by a Backend maintainer
• End-to-end tests pass (package-and-qa manual pipeline job)

What are the relevant issue numbers?

Related https://gitlab.com/gitlab-org/gitlab-ce/issues/45318