Moves the pipelines.json endpoint to startup js

What does this MR do?

Moves the pipeline.json endpoint call earlier as to allow the entire pipelines table to load faster

This work is similar to the one in this MR !62068 (merged)

Screenshots (strongly suggested)

Before	After

Note: Testing locally produces very inconsistent results, but the main idea is to move the load of pipelines.json earlier in the timeline

Does this MR meet the acceptance criteria?

Conformity

• I have included a changelog entry, or it's not needed. (Does this MR need a changelog?)
• I have self-reviewed this MR per code review guidelines.
• This MR does not harm performance, or I have asked a reviewer to help assess the performance impact. (Merge request performance guidelines)
• I have followed the style guides.