Thanks for this. This worked for us.
However I found we needed to delete both the old and new locations. On our server we had decided to install SonarQube 7.7 under a different home directory. We found we needed to also delete the old SonarQube 6.7 folders too.
Removed:
SQ_6.7_HOME/data/es5
SQ_7.7_HOME/data/es6