Revert "Testing fix for EPOS4 external"

This reverts commit 920cf42.

Author: jackal1-66

MC/config/examples/epos4/epos.sh

@@ -27,4 +27,4 @@ if [ $seed -eq 0 ]; then
 fi
 
 # Or filters the stdout with only HepMC2 useful data
-$EPO4/scripts/epos -hepstd -s $seed $optns | sed -n 's/^\(HepMC::\|[EAUWVP] \)/\1/p'
+$EPOS4_ROOT/epos4/scripts/epos -hepstd -s $seed $optns | sed -n 's/^\(HepMC::\|[EAUWVP] \)/\1/p'