Update e2e to use a user namespace config

[juliev0]

Summary

Currently, we run one version of the e2e test which has a default UserUpgradeStrategy of "pause-and-drain". We could update that such that the default strategy is still "" (noop) but then instead have the e2e test using a User Namespace file that overrides with "pause-and-drain".

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[juliev0]

@xdevxy are you okay with @dpadhiar works on this one prior to the "no data loss" test? This will confirm that the User Strategy file is working