Add a note regarding renaming `CI/CD minutes` to `compute credits`

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CI/CD minutes is being renamed to compute credits. Adding a note to clarify references.

Slack thread: https://gitlab.slack.com/archives/C01HVERGVH6/p1679329813163489

Relates to: gitlab-com/Product#5218 (closed)

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doc/ci/pipelines/cicd_minutes.md

@@ -7,6 +7,9 @@ type: reference
 
 # CI/CD minutes quota **(PREMIUM)**
 
+NOTE:
+`CI/CD minutes` is being renamed to `compute credits`. During this transition, you might see references in the UI and documentation to `CI minutes`, `CI/CD minutes`, `pipeline minutes`, `CI pipeline minutes`, and `compute credits`. All of these terms refer to compute credits.
+
 Administrators can limit the amount of time that projects can use to run jobs on
 [shared runners](../runners/runners_scope.md#shared-runners) each month. This limit
 is tracked with a quota of CI/CD minutes.