[BE] Test for broken links in harvested assets

[ioggstream]

I expect

Periodically test that accessURLs are valid on schema.gov.it/sparql

prefix dcat: <http://www.w3.org/ns/dcat#> 

select distinct ?url where {
_:a1 dcat:accessURL ?url

} 

Current behavior

no tests

Possible solution

add a gh action running a sparql query and testing all the retrieved URLs

[ioggstream]

This is part of a set of basic tests that should be implemented
to ensure the correct working of the platform.

For example, running this query right now, I found this URL

https://schema.gov.it/lodview/controlled-vocabulary/classifications-for-organizations/ateco-2007WoD
-> https://unece-stardog.ichec.ie/Ateco2007Classification#!/query/

That is referencing a nxdomain.

Probably, accessURL domains should be declared/whitelisted in some way (e.g., to inhibit referencing potentially malicious resources).