Fix a path issue in the README.md
Fix a path issue in the README.md

The instructions say 'go into the repository root folder' (which is ebr/),
but then ebr/ is used in the path on the mvn build line.

Signed-off-by: Ian Bull <703461b8006721576594feda333748873506c8ae@eclipsesource.com>

DataInMotion/ebr,fwaibel/ebr,DataInMotion/ebr,fwaibel/ebr,fwaibel/ebr,DataInMotion/ebr,DataInMotion/ebr,fwaibel/ebr