[O11y][Cassandra] Migrate Overview dashboard visualizations to lens in kibana 8.3.0 (#5714)

* Migrate overview dashboard to lens

* Update changelog

* Resize panels and truncate legends

Author: rajvi-patel-22

packages/cassandra/changelog.yml

@@ -1,3 +1,9 @@
+# newer versions go on top
+- version: "1.5.0"
+  changes:
+    - description: Migrate `Overview` dashboard visualizations to lens.
+      type: enhancement
+      link: https://github.com/elastic/integrations/pull/5714
 - version: "1.4.1"
   changes:
     - description: Added categories and/or subcategories.