fsstress-gocryptfs: fuse-xfstests now lives in /opt

fuse-xfstests should be installed to /opt now to make
the terminal output independent of the user name
(as done in https://github.com/rfjakob/fuse-xfstests/wiki/results_2021-06-02 )

tests/stress_tests/fsstress-gocryptfs.bash

@@ -23,7 +23,7 @@ MYNAME=$(basename $0)
 source ../fuse-unmount.bash
 
 # fsstress binary
-FSSTRESS=$HOME/fuse-xfstests/ltp/fsstress
+FSSTRESS=/opt/fuse-xfstests/ltp/fsstress
 if [[ ! -x $FSSTRESS ]]
 then
 	echo "$MYNAME: fsstress binary not found at $FSSTRESS"