set_zero! instead of reset_du

[DanielDoehring]

Closes #1818

[github-actions]

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[JoshuaLampert]

Thanks!

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 96.85%. Comparing base (01dfdb3) to head (381e1e7).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2670   +/-   ##
=======================================
  Coverage   96.85%   96.85%           
=======================================
  Files         546      546           
  Lines       43246    43246           
=======================================
  Hits        41885    41885           
  Misses       1361     1361           

Flag	Coverage Δ
unittests	96.85% <100.00%> (ø)

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[bennibolm]

Thanks.

[ranocha]

Thanks, this is reasonable. However, TrixiShallowWater.jl uses it, so we have to adapt their code accordingly. The easiest solution would be to do this in a breaking release.

[andrewwinters5000]

TrixiAtmo uses reset_du! as well, e.g., here. So it should probably update accordingly to avoid future issues.