[lenaploetzke]

Closes #2643

Describe your changes here:

1. Fix: Users now cant repartition element data by hand, they should use the commit function for this.
2. If the variable data_set was not the same on all processes, e.g. because of empty processes, we can run into problems because of collective function calls, e.g. repartition element data.

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 83.08%. Comparing base (fb60a9b) to head (8797a7c).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2641   +/-   ##
=======================================
  Coverage   83.07%   83.08%           
=======================================
  Files         148      148           
  Lines       22274    22276    +2     
=======================================
+ Hits        18505    18507    +2     
  Misses       3769     3769           

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[spenke91]

Looks good to me👍