Minor adjustment to debugging output in Sim1d.cpp for log levels >7

[wandadars]

Changes proposed in this pull request

I added the "true" overwrite flag to the debugging save() and saveResidual() calls in the Sim1d.cpp file to prevent code-stopping errors. I cam across this when trying to debug my work in #1622 . @ischoegl suggested putting the changes in a separate pull request.

To reproduce the error, run a 1D flow case that experiences failures in the steady newton solve, after taking a few successful newton solves. The error consists of the data group at the highest level already existing in the debug file, causing the code to error out.

Checklist

• [ ] The pull request includes a clear description of this code change
• [ ] Commit messages have short titles and reference relevant issues
• [ ] Build passes (scons build & scons test) and unit tests address code coverage
• [ ] Style & formatting of contributed code follows contributing guidelines
• [ ] The pull request is ready for review

[codecov[bot]]

Codecov Report

Attention: 4 lines in your changes are missing coverage. Please review.

Comparison is base (7efb996) 72.75% compared to head (6604a7e) 72.76%.

Files	Patch %	Lines
src/oneD/Sim1D.cpp	0.00%	4 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #1660 +/- ## ======================================= Coverage 72.75% 72.76% ======================================= Files 375 375 Lines 56584 56584 Branches 20494 20494 ======================================= + Hits 41168 41171 +3 + Misses 12401 12399 -2 + Partials 3015 3014 -1 ```

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