Update Apache Spark 3.5 runtime status to GA

Author: ms-arali

articles/synapse-analytics/toc.yml

@@ -736,7 +736,7 @@ items:
       items:
         - name: Runtime for Apache Spark overview
           href: ./spark/apache-spark-version-support.md
-        - name: Azure Synapse Apache Spark 3.5 runtime (Public Preview)
+        - name: Azure Synapse Apache Spark 3.5 runtime (GA)
           href: ./spark/apache-spark-35-runtime.md          
         - name: Azure Synapse Apache Spark 3.4 runtime (EOSA)
           href: ./spark/apache-spark-34-runtime.md