add video link (#124)

Signed-off-by: aditya109 <adikid1996@gmail.com>

charts/generic/node-drain/node-drain.chartserviceversion.yaml

@@ -34,6 +34,8 @@ spec:
       url: https://github.com/litmuschaos/litmus/tree/master/experiments/generic/node_drain
     - name: Documentation
       url: https://docs.litmuschaos.io/docs/node-drain/
+    - name: Video
+      url:
   icon:
     - url: ""
       mediatype: ""