Update all Meltano tests to not send Google Analytics Events
At the moment, every time our tests run, we generate 25 unique events from a couple different projects (with different project IDs).
We should have GA tracking turned off when tests run.
This issue should build on top of the implementation done for #650 (closed) and also turn off tracking for the test projects even when the ENV variable is not set.
Edited by Yannis Roussos