* Adding best_compression (#49974)
This commit adds a `codec` parameter to the ILM `forcemerge` action. When setting the codec to `best_compression` ILM will close the index, then update the codec setting, re-open the index, and finally perform a force merge.
* Fix ForceMergeAction toSteps construction (#51825)
There was a duplicate force merge step and the test continued to fail. This commit clarifies the
`toStep` method and changes the `assertBestCompression` method for better readability.
Resolves#51822
* Update version constants
Co-authored-by: Sivagurunathan Velayutham <sivadeva.93@gmail.com>