Date Formatter is Wrong: YYYY instead of yyyy

[ErMejo74]

As noticed by Dr. Andrew Sempere you have a glaring mistake in the date formatter.

As explained by Apple's documentation:

. A common mistake is to use YYYY. yyyy specifies the calendar year whereas YYYY specifies the year (of “Week of Year”), used in the ISO year-week calendar. In most cases, yyyy and YYYY yield the same number, however they may be different. Typically you should use the calendar year.

So, all these format strings should contain yyyy and not YYYY:

:~/swisscovid-app-ios$ fgrep -r YYYY *
DP3TApp/Screens/Homescreen/InformBroadcast/CheckInSelection/CheckInSelectionViewController.swift:        formatter.dateFormat = "dd.mm.YYYY"
DP3TApp/Logic/Helpers/DateFormatter.swift:        dateFormatter.dateFormat = "dd.MM.YYYY"
DP3TApp/Logic/Helpers/DateFormatter.swift:        dateFormatter.dateFormat = "dd. MMMM YYYY"
DP3TApp/Logic/CheckIn/ProblematicEventsManager.swift:        formatter.dateFormat = "E, dd MMM YYYY HH:mm:ss zzz"

[stmitt]

Thank you very much for raising this issue. You are right we are using the wrong year specifier, therefore exposures could have been displayed with the wrong year.
I fixed the Issue with PR #506.