Added ability to retrieve partial results from optimizer

[pbartosik]

Description

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Fixes # (issue)

Any Newly Introduced Dependencies

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How Has This Been Tested?

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Checklist:

• I agree to use the MIT license for my code changes.
• I have not introduced any 3rd party components incompatible with MIT.
• I have not included any company confidential information, trade secret, password or security token.
• I have performed a self-review of my code.

[oonyshch]

LGTM, approving.

please consider adding not only a deprecation warning for the removal of
set_search_duration()
but also stating in the docs that it has changed
maybe in a separate PR.
or let's ask the docs team @kblaszczak-intel