final write added for opt workflows

[PaulTalbot-INL]

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Pull Request Description

What issue does this change request address?

Closes #240

What are the significant changes in functionality due to this change request?

Adds final write of optimization path CSV after the RAVEN Outer MultiRun finishes, which will allow user viewing of the final accepted point.

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For Change Control Board: Change Request Review

The following review must be completed by an authorized member of the Change Control Board.

• 1. Review all computer code.
• 2. If any changes occur to the input syntax, there must be an accompanying change to the user manual and xsd schema. If the input syntax change deprecates existing input files, a conversion script needs to be added (see Conversion Scripts).
• 3. Make sure the Python code and commenting standards are respected (camelBack, etc.) - See on the wiki for details.
• 4. Automated Tests should pass.
• 5. If significant functionality is added, there must be tests added to check this. Tests should cover all possible options. Multiple short tests are preferred over one large tes.
• 6. If the change modifies or adds a requirement or a requirement based test case, the Change Control Board's Chair or designee also needs to approve the change. The requirements and the requirements test shall be in sync.
• 7. The merge request must reference an issue. If the issue is closed, the issue close checklist shall be done.
• 8. If an analytic test is changed/added, the the analytic documentation must be updated/added.
• 9. If any test used as a basis for documentation examples have been changed, the associated documentation must be reviewed and assured the text matches the example.

[PaulTalbot-INL]

@dylanjm this addresses the comments Amey had on the "final" opt point

[GabrielSoto-INL]

changes look good to me. would we have to re-gold production_flex_opt under integration_tests as well?

[PaulTalbot-INL]

Yes, you're right. It didn't show up since it's a "heavy" test. I'll regold that.

[GabrielSoto-INL]

All tests pass except for known Windows test failure in #238. LGTM, will proceed with merge