fix: adjust dead documentation link

[ThomasMinor]

Summary

Fix a dead documentation link, the puppetlabs.github.io pages seem to be gone.

[CLAassistant]

All committers have signed the CLA.

[ThomasMinor]

It seems the link is still broken, will the content be available at some time?
If yes, this PR could be closed.

[ThomasMinor]

Hi @ekohl, @bastelfreak, @smortex,
the link is still broken. If it will be fixed sometime we can close this PR, otherwise think about approving it.

[smortex]

@ThomasMinor this is currently an issue with all puppetlabs module. I asked on slack if this file is managed automatically from some internal tooling (it does not seems to be managed from pdk-templates) or if opening one PR / repo make sense but got no answer. I pinged them again.

AFAIAC, this new URL in this PR is fine, and if we have no news from people at puppetlabs, I am fine with replacing this broken link with a working one with similar content like this one.