Verify consistent use of .as().getBody()

[psmf22]

In some commands unirest command responses are cast as empty which might lead to loss of information in error cases.

An example I already fixed:

unirest.delete(SSCUrls.AUTH_ENTITIES).queryString("ids", authEntityIdsToDelete).asEmpty().getBody();

.asEmpty() should be replaced by either .asString() or .asObject(JsonNode.class). We might want to investigate which one looks better before we rework.