cleanup opf in case of non convergence

[marakasm]

Hello, this is my first PR, so don't hesitate to let me know if I need to add something, for example file an issue linked to this.

Optimal power flow was not cleaned up in case it did not converge. This implied that generators created to model dclines were not deleted. This is a problem if another opf is run afterwards.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

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[codecov]

Codecov Report

❌ Patch coverage is 0% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 72.12%. Comparing base (44d7d69) to head (2d4fbaa).

Files with missing lines	Patch %	Lines
pandapower/optimal_powerflow.py	0.00%	1 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #3084      +/-   ##
===========================================
- Coverage    72.12%   72.12%   -0.01%     
===========================================
  Files          355      355              
  Lines        39376    39377       +1     
===========================================
  Hits         28400    28400              
- Misses       10976    10977       +1     

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[vogt31337]

@marakasm , thanks for the PR. Does IT solve #3018 ?
I'll have a Look into IT later.

[marakasm]

@marakasm , thanks for the PR. Does IT solve #3018 ? I'll have a Look into IT later.

@vogt31337 I dont think this is related, I did not work on testing, and did not change convergence behavior, just added a clean up in case of non convergence.

Thanks !

[KS-HTK]

Does this solve the issue described in #3073 ?

[marakasm]

Does this solve the issue described in #3073 ?

I don't think so because the clean up that I added is related to hvdc lines and the example used in #3073 does not contain any if I am not mistaken