Update ElasticSearch README in example folder

[akankshakumari393]

Describe the bug
The elastic Search README is stale https://github.com/kanisterio/kanister/blob/master/examples/elasticsearch/README.md and not as per latest release of elastic search 8.5.1 as of creating this issue.

To Reproduce
Steps to reproduce the behavior:

1. Go to https://github.com/kanisterio/kanister/blob/master/examples/elasticsearch/README.md
2. the step mentioned to populate data gives error.

Expected behavior
The README should be working if someone follows it.

Screenshots
If applicable, add screenshots to help explain your problem.

Environment
Kubernetes Version/Provider: ...
Storage Provider: ...
Cluster Size (#nodes): ...
Data Size: ...

Additional context
Add any other context about the problem here.

[github-actions]

Thanks for opening this issue 👍. The team will review it shortly.

If this is a bug report, make sure to include clear instructions how on to reproduce the problem with minimal reproducible examples, where possible. If this is a security report, please review our security policy as outlined in SECURITY.md.

If you haven't already, please take a moment to review our project's Code of Conduct document.