Run airgapped smoke tests on gitaly cluster

What does this MR do and why?

Part of Extend gitlab-qa Airgapped tests to run against... (#694 - closed)

Modifies the Airgapped scenario to run against the GitalyCluster Scenario.

As a first iteration - this will only run against the smaller subset of smoke tests with Extend airgap to use gitaly cluster for a broad... (!1092 - merged) as a follow up to extend to a broader suite of tests

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