Revert "Add Elixir for Measurements.jl"

[vchuravy]

Reverts #2504 should remove the stochastic failure from CI until we have enough time to debug the cause (see #2524)

[github-actions]

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[JoshuaLampert]

Thanks!

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 96.76%. Comparing base (6ebd7a9) to head (fa0aa8a).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2525      +/-   ##
==========================================
+ Coverage   95.18%   96.76%   +1.58%     
==========================================
  Files         512      512              
  Lines       42388    42391       +3     
==========================================
+ Hits        40345    41016     +671     
+ Misses       2043     1375     -668     

Flag	Coverage Δ
unittests	96.76% <ø> (+1.58%)	⬆️

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[DanielDoehring]

In that case: Maybe also revert the example presented in the docs?

https://trixi-framework.github.io/TrixiDocumentation/stable/tutorials/differentiable_programming/#Propagating-errors-using-Measurements.jl

I just added the elixir to more or less test the docs - which turned out to be simultaneously a good and bad idea :D

[ranocha]

Let's see how our CI system responds to this change first. Removing the example in the docs or fixing the underlying issue can be done later.