Fixes #2758. ReSharper unit tests detects errors that VS2022 don't.

[BDisp]

Fixes #2758 - Set CultureInfo.DefaultThreadCurrentUICulture = CultureInfo.GetCultureInfo ("en-US") in the AutoInitShutdownAttribute was enough. Also fixed some typos.

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[BDisp]

But still happens this #2758 (comment) because the threads are not properly disposed.