docs: update bibtex typo

Author: bheijden

README.rst

@@ -28,7 +28,7 @@ If you are using EAGERx for your scientific publications, please cite:
 
     @article{eagerx,
         author  = {van der Heijden, Bas and Luijkx, Jelle, and Ferranti, Laura and Kober, Jens and Babuska, Robert},
-        title = {EAGER: Engine Agnostic Gym Environment for Robotics},
+        title = {EAGERx: Engine Agnostic Gym Environment for Robotics},
         year = {2022},
         publisher = {GitHub},
         journal = {GitHub repository},