Do not upload the GraphQL schema in docs-only pipelines
What does this MR do and why?
This should speed up docs-only pipelines that don't need to generate the GraphQL schema. Here's a recent pipeline where the schema was generated despite no subsequent jobs needing it: https://gitlab.com/gitlab-org/gitlab/-/pipelines/1451473702.
Related to #476864 (closed)
Edited by Paul Gascou-Vaillancourt