Update maintainers
Update maintainers

Signed-off-by: Richard Hartmann <dbc5c9b9cbc722d5250b7cedc577ded204477545@richih.org>

raintank/metrictank,raintank/raintank-metric,raintank/metrictank,raintank/metrictank,raintank/raintank-metric,raintank/metrictank,raintank/raintank-metric