Add indentation.

Author: jblueh

README.md

@@ -31,20 +31,20 @@ If you use OpDiLib in one of your applications and write a paper, please cite us
 
 ~~~~{.txt}
 @article{BluehdornSG2023,
-author = {Bl\"{u}hdorn, Johannes and Sagebaum, Max and Gauger, Nicolas R.},
-title = {{Event-Based Automatic Differentiation of OpenMP with OpDiLib}},
-year = {2023},
-issue_date = {March 2023},
-publisher = {Association for Computing Machinery},
-address = {New York, NY, USA},
-volume = {49},
-number = {1},
-url = {https://doi.org/10.1145/3570159},
-doi = {10.1145/3570159},
-journal = {ACM Trans. Math. Softw.},
-month = {mar},
-articleno = {3},
-numpages = {31}
+  author = {Bl\"{u}hdorn, Johannes and Sagebaum, Max and Gauger, Nicolas R.},
+  title = {{Event-Based Automatic Differentiation of OpenMP with OpDiLib}},
+  year = {2023},
+  issue_date = {March 2023},
+  publisher = {Association for Computing Machinery},
+  address = {New York, NY, USA},
+  volume = {49},
+  number = {1},
+  url = {https://doi.org/10.1145/3570159},
+  doi = {10.1145/3570159},
+  journal = {ACM Trans. Math. Softw.},
+  month = {mar},
+  articleno = {3},
+  numpages = {31}
 }
 ~~~~