fix(joss_paper) remove https://doi.org/ in doi entrys in paper.bib

Author: fabiencasenave

docs/joss_paper/paper.bib

@@ -3,7 +3,7 @@ @article{casenave2025physics
   author={Casenave, Fabien and Roynard, Xavier and Staber, Brian and Akkari, Nissrine and Piat, William and Bucci, Michele Alessandro and Kabalan, Abbas and Nguyen, Xuan Minh Vuong and Saverio, Luca and Perez, Rapha{\"e}l Carpintero and others},
   journal={arXiv preprint arXiv:2505.02974},
   year={2025},
-  doi={https://doi.org/10.48550/arXiv.2505.02974}
+  doi={10.48550/arXiv.2505.02974}
 }
 
 @inproceedings{poinot2018seven,
@@ -12,7 +12,7 @@ @inproceedings{poinot2018seven
   booktitle={2018 AIAA Aerospace Sciences Meeting},
   pages={1503},
   year={2018},
-  doi={https://doi.org/10.2514/6.2018-1503}
+  doi={10.2514/6.2018-1503}
 }
 
 @article{casenave2024mmgp,
@@ -31,15 +31,15 @@ @article{kabalan2025elasticity
   pages={115929},
   year={2025},
   publisher={Elsevier},
-  doi={https://doi.org/10.1016/j.apm.2025.115929}
+  doi={10.1016/j.apm.2025.115929}
 }
 
 @article{kabalan2025ommgp,
   title={{O-MMGP}: {O}ptimal {M}esh {M}orphing {G}aussian {P}rocess Regression for Solving {PDEs} with non-Parametric Geometric Variations},
   author={Kabalan, Abbas and Casenave, Fabien and Bordeu, Felipe and Ehrlacher, Virginie},
   journal={arXiv preprint arXiv:2502.11632},
   year={2025},
-  doi={https://doi.org/10.48550/arXiv.2502.11632},
+  doi={10.48550/arXiv.2502.11632},
 }
 
 @inproceedings{perez2024gaussian,
@@ -56,5 +56,5 @@ @article{perez2024learning
   author={Carpintero Perez, Rapha{\"e}l and Da Veiga, S{\'e}bastien and Garnier, Josselin and Staber, Brian},
   journal={arXiv preprint arXiv:2410.15721},
   year={2024},
-  doi={https://doi.org/10.48550/arXiv.2410.15721},
+  doi={10.48550/arXiv.2410.15721},
 }