fix type instability when iterating over callbacks in simple integrators

[ranocha]

Fixes #1679

[github-actions]

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Created with ❤️ by the Trixi.jl community.

[DanielDoehring]

I guess for consistency one should also change

Trixi.jl/src/time_integration/methods_2N.jl

Lines 122 to 127 in c2f0095

	for cb in callback.continuous_callbacks
	error("unsupported")
	end
	for cb in callback.discrete_callbacks
	cb.initialize(cb, integrator.u, integrator.t, integrator)
	end

and

Trixi.jl/src/time_integration/methods_3Sstar.jl

Lines 192 to 197 in c2f0095

	for cb in callback.continuous_callbacks
	error("unsupported")
	end
	for cb in callback.discrete_callbacks
	cb.initialize(cb, integrator.u, integrator.t, integrator)
	end

as well as

Trixi.jl/src/time_integration/methods_SSP.jl

Lines 127 to 132 in c2f0095

	for cb in callback.continuous_callbacks
	error("unsupported")
	end
	for cb in callback.discrete_callbacks
	cb.initialize(cb, integrator.u, integrator.t, integrator)
	end

and most importantly

Trixi.jl/src/time_integration/methods_SSP.jl

Lines 187 to 190 in c2f0095

	for cb in callbacks.discrete_callbacks
	if cb.condition(integrator.u, integrator.t, integrator)
	cb.affect!(integrator)
	end

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (c2f0095) 82.63% compared to head (9e17d72) 86.35%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1684      +/-   ##
==========================================
+ Coverage   82.63%   86.35%   +3.71%     
==========================================
  Files         425      425              
  Lines       34376    34366      -10     
==========================================
+ Hits        28406    29674    +1268     
+ Misses       5970     4692    -1278     

Flag	Coverage Δ
unittests	86.35% <100.00%> (+3.71%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files	Coverage Δ
src/time_integration/methods_2N.jl	90.36% <100.00%> (ø)
src/time_integration/methods_3Sstar.jl	93.27% <100.00%> (+1.92%)	⬆️

... and 214 files with indirect coverage changes

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[ranocha]

Good catch 👍 I adapted these parts as well.

[ranocha]

Thanks! It's annoying that we sometimes use plural and sometimes singular...