[trivial] move userworkbeforeloop before outputs

[Yurlungur]

PR Summary

This is a trivial change to a feature I think almost no one is using yet. One reason to use UserWorkBeforeLoop is to modify, e.g., initial conditions. If you want to see that reflected in your initial data, it needs to be before the first output. This moves it to be above the first output.

PR Checklist

• Code passes cpplint
• New features are documented.
• Adds a test for any bugs fixed. Adds tests for new features.
• Code is formatted
• Changes are summarized in CHANGELOG.md
• CI has been triggered on Darwin for performance regression tests.
• Docs build
• (@lanl.gov employees) Update copyright on changed files

[bprather]

Technically breaks downstream

[lroberts36]

LGTM