Broken link in Docker hub Telegraf description page

[Cougar]

Link from Docker hub points to https://docs.influxdata.com/telegraf/latest/introduction/getting_started/ which redirects to missing page https://docs.influxdata.com/telegraf/v1.18/introduction/getting_started/ that suggests to open a case here.

[kelseiv]

Thank you, @Cougar! submitted PR to fix this link

[kelseiv]

Updated the wrong file in PR above.
New PR to resolve this issue merged: docker-library/docs#1929