Add pipeline status to projects GraphQL query

Background

In &13066 (closed) we are moving Your work -> Projects to Vue and using GraphQL as the data source. This will allow us to have UX parity across the product, implement filters more easily, and reduce technical debit. We need to be able to get the pipeline status for projects from the GraphQL query but this is not possible at the moment.

Proposal

Add pipeline_status field to app/graphql/types/project_type.rb that uses the cached pipeline status from app/models/project.rb#L2398. See !164943 (closed) for a POC.

Implementation guide

See !164943 (closed)