Another page break tweak

Author: bonachea

doc/joss/paper.md

@@ -212,4 +212,5 @@ This material is also based on work supported by Laboratory Directed Research an
 This manuscript has been authored by an author at Lawrence Berkeley National Laboratory under Contract No. DE-AC02-05CH11231 with the U.S. Department of Energy.
 The U.S. Government retains, and the publisher, by accepting the article for publication, acknowledges, that the U.S. Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for U.S. Government purposes.
 
+\clearpage
 # References