Threshold Expert test uses hardcoded Redis host

[wagner-intevation]

intelmq/intelmq/tests/bots/experts/threshold/test_expert.py

Line 38 in 79cae29

'redis_cache_host': '127.0.0.1',

Instead of using 127.0.0.1, INTELMQ_PIPELINE_HOST should be used, as done by other tests, to support running tests with redis on different hosts, e.g. in docker setups