Update legendLink
Update legendLink

This still had the 'k8s' in as it was copied and pasted from the
kubernetes-mixin.

Signed-off-by: beorn7 <91e32ae1d26bd312b370cf8378a5a83accca90a0@grafana.com>

siavashs/node_exporter,siavashs/node_exporter,prometheus/node_exporter,siavashs/node_exporter,siavashs/node_exporter,prometheus/node_exporter,prometheus/node_exporter