Update pythia8 to include Heavy other matching patch.

cms-externals/pythia8@e7fed8b

pythia8.spec

@@ -2,7 +2,7 @@
 
 Requires: hepmc lhapdf
 
-%define tag 2c5a4f204767dfd62849eb01c9b70b4ff16311a9
+%define tag e7fed8bd8d0fc89a59c8d5e5020370b4d2d50649
 %define branch cms/%{realversion}
 %define github_user cms-externals
 Source: git+https://github.com/%github_user/%{n}.git?obj=%{branch}/%{tag}&export=%{n}-%{realversion}&output=/%{n}-%{realversion}.tgz