Update the button name `Run pipeline`

Summary

Related #480009 (comment 2086664659)

• It's misleading to say Run when we are not actually going to run the pipeline.

Definition of Done

• Users will see the new button name New pipeline in the Build > Pipeline tab when landing on the new page

  Current screenshot

  

• Users will see the new tooltip name Run scheduled pipeline in the Build > Pipeline schedule on hover the button ⏯️
  (Completed with !169492 (merged))

  Current screenshot

  

Details

Some candidates:

• create pipeline
• new pipeline

Reference in GitLab docs

Roles involved

• Design
• Technical Writing
• Backend
• Frontend
• Test engineering

NOTE: When work is ready to be defined, please create appropriate sub-tasks.