lint yaml files

.yamllint

dhcp-server/defaults/main.yml

dhcp-server/tasks/main.yml

mrtg/defaults/main.yml

mrtg/tasks/main.yml

mrtg/tasks/weathermap.yml

networkd/defaults/main.yml

networkd/handlers/main.yml

networkd/tasks/main.yml

radius-client/handlers/main.yml

radius-client/tasks/main.yml

radius-server/defaults/main.yml

radius-server/tasks/main.yml