fix(test): move reading env variable inside method

[anshbansal]

In case we try to run this in a kubernetes environment this causes failures

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All modified and coverable lines are covered by tests ✅

✅ All tests successful. No failed tests found.

see 1 file with indirect coverage changes

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[david-leifker]

This should likely be converted to a test fixture. Resolve it once, lazy or not, but then inject it into the tests like we did for the graph_client and auth_session. This way it would not only be resolved when needed but then only by the tests which require it.

[anshbansal]

If we make it a test fixture then it will still try to resolve it. That is not needed for the cases where USE_STATIC_SLEEP = true