adding missing toc entries

Author: julieMSFT

articles/synapse-analytics/toc.yml

@@ -322,6 +322,10 @@
         href: ./data-integration/linked-service.md
   - name: Manage and monitor
     items:
+    - name: Pipeline runs
+      href: monitoring/how-to-monitor-pipeline-runs.md
+    - name: Spark applications
+      href: monitoring/how-to-monitor-spark-applications.md
     - name: Synapse SQL
       items:
       - name: Monitor Gen2 cache