set back to maven-bundle-plugin release version
set back to maven-bundle-plugin release version

snapshot hinders client prjoect plugins :(

Signed-off-by: Andreas Pieber <57efbcbb22ec0bd89955a40df26b44c340d3e38d@gmail.com>

openengsb/openengsb-root,openengsb/openengsb-root,GitHub2020/openengsb-root,GitHub2020/openengsb-root