Remove :new_pipeline_graph FF
What does this MR do and why?
Removes the feature flag :new_pipeline_graph of [Feature flag] Redesigned Pipeline Graph (#426902)
MR acceptance checklist
Please evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.
Screenshots or screen recordings
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How to set up and validate locally
- Check out a pipeline graph page, e.g. http://gdk.test:3000/flightjs/Flight/-/pipelines/9
Related to #425467 (closed), gitlab-com/www-gitlab-com!133679 (merged), #426902