Added optimization for Opensearch and also included the options to tweak the hyper parameters

[navneet1v]

Description

This change includes the following things:

1. Added the refresh and force merge functions to improve the performance of Opensearch.
2. Added the parameter tuning options while selecting a test from UI.

Next steps:

1. Add the support for updating the shards and replicas for the index.

[navneet1v]

/assign @XuanYang-cn

[alwayslove2013]

@navneet1v @jmazanec15 Great contribution! This will really help community users test AWS OpenSearch.

[sre-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: alwayslove2013, jmazanec15, navneet1v
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