[releng] Fix Maven <repository> ID

A name clash was introduced recently, as repo.eclipse.org is now used
within the HIPP's settings.xml. See
<https://repo.eclipse.org/content/repositories/recommenders-releases/>
for background.

Change-Id: I404348260eaed90a0d79515f257b373c51d21822
Signed-off-by: Andreas Sewe <andreas.sewe@codetrails.com>