add stabilizer for G-sets

[ThomasBreuer]

resolves #3259

[codecov]

Codecov Report

Attention: Patch coverage is 86.95652% with 3 lines in your changes missing coverage. Please review.

Project coverage is 84.60%. Comparing base (24c8f63) to head (8d54838).
Report is 2 commits behind head on master.

Files with missing lines	Patch %	Lines
src/Groups/action.jl	78.57%	3 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #4206   +/-   ##
=======================================
  Coverage   84.59%   84.60%           
=======================================
  Files         631      631           
  Lines       84906    84915    +9     
=======================================
+ Hits        71830    71842   +12     
+ Misses      13076    13073    -3     

Files with missing lines	Coverage Δ
src/GAP/wrappers.jl	94.94% <100.00%> (+0.03%)	⬆️
src/Groups/gsets.jl	91.57% <100.00%> (+0.22%)	⬆️
src/Groups/action.jl	97.16% <78.57%> (ø)

... and 2 files with indirect coverage changes

[ThomasBreuer]

One test failed because it was canceled after 2 1/2 hours (test (nightly, book, ubuntu-latest).
Since this pull request introduced a new feature that cannot be used in these tests, I think that the proposed changes are not responsible for slowing down the test.

[benlorenz]

One test failed because it was canceled after 2 1/2 hours (test (nightly, book, ubuntu-latest). Since this pull request introduced a new feature that cannot be used in these tests, I think that the proposed changes are not responsible for slowing down the test.

I have seen this happen in the scheduled tests on master as well: https://github.com/oscar-system/Oscar.jl/actions/runs/11285680359/job/31388879146

[joschmitt]

The failing test seems unrelated because it also fails on master, so I merge this now.