Create function for last updated separately

I ran into the closure inside a loop problem, again. I have moved the
closure into a separate function with the appropriate metric arguments.
This way the value gets bound and everything works as expected.

Signed-off-by: Konrad Reiche <konrad.reiche@gmail.com>
Only fetch required fields for link checker

For a more efficient preprocessing phase only the required fields,
namely id and resources.url are retrieved for the link checker metric.
Also I have added the no timeout call.

The link checker takes a long time until are requests are finished.
While executing the requests, the query loop is still open which seems
to time out at some point. Then the application hangs, hence the
no_timeout command.

Signed-off-by: Konrad Reiche <konrad.reiche@gmail.com>