Updates to library surfaced failing tests

[bcoe]

Prior to the updates in https://github.com/googleapis/nodejs-vision/pull/1016, only the product sets suite of tests was running in integration.

When all tests were enabled, many flaky/failing tests have been surfaced.

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Note: when fixing tests we should also ensure that resources created during test runs are cleaned, I believe vision has likely been leaking resources for quite some time.