Update joss_paper/paper.bib

Co-authored-by: Marie Weiel <marie.weiel@kit.edu>

Author: MarleneBusch

joss_paper/paper.bib

@@ -121,7 +121,7 @@ @article{Lewen:2025
     author = {Lewen, Jan and Pargmann, Max and Maldonado Quinto, Daniel and Jitsev, Jenia and Cherti, Mehdi and Pitz-Paal, Robert},
     journal = {Solar Energy},
     year = {2025},
-    month = {M{\"a}rz},
+    month = {March},
     doi = {10.1016/j.solener.2025.113312},
     keywords = {Inverse Deep Learning Raytracing, Deep Learning, Heliostat Surface Errors, Concentrating Solar Power},
     issn = {0038-092X}