Use localized strings in UI tests

[stefanceriu]

We are currently doing a lot of work around custom bundle handling in order to get our localizable strings to work properly. We would like to investigate ways of simplifying the flows, removing some of the code and relying more on default bundles and plain NSLocalizedString.

[ismailgulek]

We've tried base localization but found out that it doesn't work key-based. So it'll fail for missing translations on some languages. We'll keep it as is for now and in the context of this issue, we'll just target localizations in UI tests and use them when checking UI elements.