Doc: Helion Credits (#5688)

Scientists from Helion have and continue to contribute major features
and bug fixes to WarpX. Add them to institutional acknowledgements.

Author: ax3l

Docs/source/acknowledge_us.rst

@@ -23,15 +23,15 @@ Please add the following sentence to your publications, it helps contributors ke
 
 **Plain text:**
 
-  This research used the open-source particle-in-cell code WarpX https://github.com/ECP-WarpX/WarpX. Primary WarpX contributors are with LBNL, LLNL, CEA-LIDYL, SLAC, DESY, CERN, and TAE Technologies. We acknowledge all WarpX contributors.
+  This research used the open-source particle-in-cell code WarpX https://github.com/ECP-WarpX/WarpX. Primary WarpX contributors are with LBNL, LLNL, CEA-LIDYL, SLAC, DESY, CERN, Helion Energy, and TAE Technologies. We acknowledge all WarpX contributors.
 
 **LaTeX:**
 
 .. code-block:: latex
 
   \usepackage{hyperref}
   This research used the open-source particle-in-cell code WarpX \url{https://github.com/ECP-WarpX/WarpX}.
-  Primary WarpX contributors are with LBNL, LLNL, CEA-LIDYL, SLAC, DESY, CERN, and TAE Technologies.
+  Primary WarpX contributors are with LBNL, LLNL, CEA-LIDYL, SLAC, DESY, CERN, Helion Energy, and TAE Technologies.
   We acknowledge all WarpX contributors.
 
 .. _acknowledge_warpx_ref: