chore(NA): update ci step name to Check Public API Docs (#144573)

Co-authored-by: Kibana Machine <42973632+kibanamachine@users.noreply.github.com>

.buildkite/pipelines/on_merge.yml

@@ -39,8 +39,8 @@ steps:
         - exit_status: '*'
           limit: 1
 
-  - command: .buildkite/scripts/steps/on_merge_ts_refs_api_docs.sh
-    label: Build TS Refs and Check Public API Docs
+  - command: .buildkite/scripts/steps/on_merge_api_docs.sh
+    label: Check Public API Docs
     key: public-api-docs
     agents:
       queue: n2-4-spot