Write failed solution when `restart_failed_analysis` is False

Purpose

In the MPhys wrapper, there is an option to try clean restarting an analysis that stalls/fails to converge. In those cases, the failed solution is written so the user can try to figure out what went wrong. However, no failed solution is written when restart_failed_analysis is False (this is the default), making diagnosis challenging. This PR changes it so a solution is written in this case.

Expected time until merged

A few days

Type of change

[ ] Bugfix (non-breaking change which fixes an issue)
[x] New feature (non-breaking change which adds functionality)
[ ] Breaking change (non-backwards-compatible fix or feature)
[ ] Code style update (formatting, renaming)
[ ] Refactoring (no functional changes, no API changes)
[ ] Documentation update
[ ] Maintenance update
[ ] Other (please describe)

Testing

Run an MPhys ADflow case where the restart_failed_analysis option in the ADflowBuilder is set to False and set the max number of ADflow iterations to a very small number so it fails to converge. Before this PR, you will see no failed analysis solution written. With the PR, you will.

Checklist

[ ] I have run flake8 and black to make sure the Python code adheres to PEP-8 and is consistently formatted
[ ] I have formatted the Fortran code with fprettify or C/C++ code with clang-format as applicable
[ ] I have run unit and regression tests which pass locally with my changes
[ ] I have added new tests that prove my fix is effective or that my feature works
[ ] I have added necessary documentation

Codecov Report

Attention: Patch coverage is 0% with 2 lines in your changes are missing coverage. Please review.

Project coverage is 41.47%. Comparing base (de01140) to head (83121a7).

Files	Patch %	Lines
adflow/mphys/mphys_adflow.py	0.00%	2 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #343 +/- ## ========================================== - Coverage 41.49% 41.47% -0.03% ========================================== Files 13 13 Lines 4066 4068 +2 ========================================== Hits 1687 1687 - Misses 2379 2381 +2 ```

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mdolab / adflow