Adding a section for OpenSearch SQL CLI on Downloads/Getting Started page to fix #654

[vimalMK]

Signed-off-by: Vimal K [email protected]

Description

Add a section for OpenSearch SQL CLI on Downloads/Getting Started page

The new section looks as follows:

The brief descriptive words for this cli tool was taken from https://pypi.org/project/opensearchsql/ . I did not had that information so I took the liberty to add what I feel fits well for the section. The platform and package information is also added, open to change those if required. This is my very first contribution to OpenSearch project , so please let me know if anything has to be changed . Thank you

Issues Resolved

Closes #654

Check List

• [ ] Commits are signed per the DCO using --signoff

By submitting this pull request, I confirm that my contribution is made under the terms of the BSD-3-Clause License.