Add downstream tests for TrixiShallowWater.jl

[sloede]

In preparation of the upcoming Trixi.jl <--> TrixiShallowWater.jl split.

[github-actions]

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Created with ❤️ by the Trixi.jl community.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (c79fa43) 72.65% compared to head (ce522c4) 83.05%.

Additional details and impacted files

@@             Coverage Diff             @@
##             main    #1707       +/-   ##
===========================================
+ Coverage   72.65%   83.05%   +10.40%     
===========================================
  Files         431      431               
  Lines       34637    34665       +28     
===========================================
+ Hits        25164    28791     +3627     
+ Misses       9473     5874     -3599     

Flag	Coverage Δ
unittests	83.05% <ø> (+10.40%)	⬆️

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see 116 files with indirect coverage changes

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[ranocha]

Thanks! Looks good to me - except the failing CI tests we observe also in other PRs...

[sloede]

Thanks! Looks good to me - except the failing CI tests we observe also in other PRs...

Since this is not a breaking change nor affecting any tests, I suggest we go ahead and merge it to get it out of the way...