docs(pipeline): describe pipeline deletion via UI

doc/ci/pipelines.md

@@ -305,12 +305,14 @@ For example, the query string
 ### Accessing pipelines
 
 You can find the current and historical pipeline runs under your project's
-**CI/CD > Pipelines** page. Clicking on a pipeline will show the jobs that were run for
-that pipeline.
+**CI/CD > Pipelines** page. You can also access pipelines for a merge request by navigating
+to its **Pipelines** tab.
 
 ![Pipelines index page](img/pipelines_index.png)
 
-You can also access pipelines for a merge request by navigating to its **Pipelines** tab.
+Clicking on a pipeline will bring you to the **Pipeline Details** page and show
+the jobs that were run for that pipeline. From here you can cancel a running pipeline,
+retry jobs on a failed pipeline, or [delete a pipeline](#deleting-a-single-pipeline).
 
 ### Accessing individual jobs
 
@@ -412,11 +414,17 @@ This functionality is only available:
 
 ### Deleting a single pipeline
 
-> [Introduced](https://gitlab.com/gitlab-org/gitlab/merge_requests/21365) in GitLab 12.6.
+> [Introduced](https://gitlab.com/gitlab-org/gitlab/issues/24851) in GitLab 12.7.
 
-Users with at least Owner access can delete a pipeline and all related child objects,
-such as jobs and artifacts. Deleting a pipeline is done via **Delete** button on the
-pipeline detail view.
+Users with [owner permissions](../user/permissions.md) in a project can delete a pipeline
+by clicking on the pipeline in the **CI/CD > Pipelines** to get to the **Pipeline Details**
+page, then using the **Delete** button.
+
+![Pipeline Delete Button](img/pipeline-delete.png)
+
+CAUTION: **Warning:**
+Deleting a pipeline will expire all pipeline caches, and delete all related objects,
+such as builds, logs, artifacts and triggers. **This action cannot be undone.**
 
 ## Most Recent Pipeline