[beats receivers] Add integration test that confirms data can be sent through the translated logstash exporter #13019
Description
Once #12739 merges, let's add an integration test to the agent repository to ensure Hybrid Agent can write data through a real instance of Logstash.
If not already covered, this test should check for document equivalence between the logstash output and exporter like the existing Elasticsearch tests do.
It may be easiest to do this in the Kubernetes tests so Logstash can be added as a container. There is nothing platform specific about the Logstash translation so testing only on Linux feels reasonable.
Another option would be ensuring Logstash is available in the base VMs for testing, or just downloading and installing it as part of the test.