Refactor time integrator 2N and 3Star more similar to OrdinaryDiffEq.jl integrators

[warisa-r]

Closes #1886 by @DanielDoehring , this PR makes changes to the integrator in method2N.jl and methods_3Sstar.jl.

Please let me know if there is something wrong or any changes have to be made!

[github-actions]

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[ranocha]

Thanks. Please find some comments below. Additionally, it would be nice to test the new functionality for the use case motivating this change.

[codecov]

Codecov Report

Attention: Patch coverage is 95.00000% with 4 lines in your changes missing coverage. Please review.

Project coverage is 96.16%. Comparing base (75d8c67) to head (a169e57).

Files	Patch %	Lines
src/time_integration/methods_2N.jl	94.74%	2 Missing ⚠️
src/time_integration/methods_3Sstar.jl	95.24%	2 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1975   +/-   ##
=======================================
  Coverage   96.16%   96.16%           
=======================================
  Files         460      460           
  Lines       36957    36971   +14     
=======================================
+ Hits        35537    35551   +14     
  Misses       1420     1420           

Flag	Coverage Δ
unittests	96.16% <95.00%> (+<0.01%)	⬆️

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[ranocha]

Thanks!

[ranocha]

Could you please run the formatter?

[ranocha]

Could you please add your name to our list of authors?

https://github.com/trixi-framework/Trixi.jl/blob/main/AUTHORS.md

[DanielDoehring]

Thanks for doing this!

[ranocha]

Thanks!