Pipeline Graph Structural Update: Unify Apollo Providers

What does this MR do?

Unifies Apollo providers across the main pipeline graph, pipeline header, and needs (DAG) graph. Also, updates the pipeline header to make use of the etag poll caching option used by the pipeline graph.

Does this MR meet the acceptance criteria?

Conformity

• 📋 Does this MR need a changelog?
  • I have included a changelog entry.
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Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.

Related to #276949 (closed)