Use a version of CultureScope that doesn't have user overrides (OSOE-350)

[sarahelsaig]

This is related to OrchardCMS/OrchardCore#11228
The useUserOverride in CultureInfo(string Culture, bool useUserOverride) should be always false in UI tests to make them more reproducible and portable. Depending on how the above linked issue goes, we should either force default configuration or replace it with a custom implementation that uses the method suggested in the issue description.

After this, this line in Data Tables needs to be changed too.

Jira issue

[Piedone]

Once OrchardCMS/OrchardCore#12467 is merge, I think we can just update the _appsettings.json_s (the root ones) for our sites, and update the docs here to recommend that.