Issue Description:

When using a Jenkins Declarative Pipeline with parallel stages, I have encountered an issue where the Blue Ocean UI does not display all the defined stages. Specifically, when the pull_dp_code stage is included within the parallel construct, the subsequent post_parallel stage does not appear in the Blue Ocean UI. However, if I remove the pull_dp_code stage from the parallel structure, the post_parallel stage becomes visible.

Steps to Reproduce:

1. Create a Jenkins Declarative Pipeline that includes parallel stages.
2. Include multiple stages within the parallel construct.
3. Run the pipeline in Blue Ocean UI.
4. Observe if certain stages do not appear in the UI.

Expected Behavior: All defined stages, whether standalone or within a parallel construct, should be correctly displayed in the Blue Ocean UI.

Actual Behavior: When the parallel construct includes certain stages (e.g., pull_dp_code), subsequent stages (e.g., post_parallel) are not displayed in the Blue Ocean UI.