Add tests to catch not-compacted properties

[acka47]

As said in #163 (comment) we need some mechanism to check whether all properties are compacted in the lobid-gnd JSON-LD or whether some keys exist that are a URI.

This might best be implemented using the GET mapping mechanism.

[acka47]

See #89 (comment) as current case where we have problems with not automatically detecting not-compacted keys. (Although I knew about this change and should have prepared the context, a test would of course be fine to catch it when we miss something.)

[acka47]

The tests should at best run before a new index is deployed to production.

[acka47]

As discussed today, this is a good issue for @dr0i to help out with lobid-gnd.

[dr0i]

quick note: curl weywot5.hbz-nrw.de:9200/gnd/_mapping | jq -r 'paths | map(.|tostring)|join(".")' |grep http.*properties. |grep -vE '.properties(.id|.label)(.*)$' |grep -vE '.properties$'
where have to get the proper index name of course.

[dr0i]

As mailing was not working on quaoar1: uninstalled postfix and installed sendmail.

[dr0i]

TODO: get/set index-name which shall be checked.