Fix regression test; can't get tag when the connection's not actually…

[derekwbrown]

What does this PR do?

Fixes unit test that was checking for the new cluster tag on the test to a bad port.

[yannmh]

We are not using the same tag set for service checks as a function of the status. This is actually an issue.
For instance, the following monitor would only return OK (best case a NO DATA if set):

elasticsearch.can_connect by {cluster_name}

In short: let's remove this tag from all service checks.

cc @degemer

[degemer]

Tests are 💚 , sky is 🔵 , let's merge this!