Fix simulation restart when using averaging

[blaisb]

Description

There was an issue where simulation restarts would crash on large parallel simulation when the time-averaging of the velocity was enabled. This issue was caused by the fact that the vectors that were checkpointed were the locally_relevant solutions but the restart was reading into the locally_owned solutions.

Solution

I have fixed this by reading the restart into the locally_relevant solutions. However, I had to add a function to manually sanitize the time_averaging operator because the locally_owned vectors were now empty.

Testing

This should not affect any of the current test results. I do not know if it is necessary to add a new tests since restart tests are cumbersome. @lpsaavedra what do you think?

Documentation

No changes to documentation.

Miscellaneous (will be removed when merged)

Checklist (will be removed when merged)

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Code related list:

• All in-code documentation related to this PR is up to date (Doxygen format)
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• Fix has unit test(s) (preferred) or application test(s), and restart files are in the generator folder
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[lpsaavedra]

Good that you found this bug. I don't think we need to add more tests since we already have restart tests and it is not easy to reproduce with small cases.