Refresh room summaries when date or time changes in the device (#3683)

* Add `DateTimeObserver` to rebuild the room summary data when the date/time changes.

* Add time changed action too, to trigger when the user manually changes date/time

* Fix timezone issue by adding `TimezoneProvider`, fix tests

* Create test for `DateTimeObserver` usage in `RoomListDataSource`

* Create aRoomListRoomSummaryFactory function.

* Improve test by faking the lastMessageTimestampFormatter

---------

Co-authored-by: Benoit Marty <benoit@matrix.org>

libraries/eventformatter/api/src/main/kotlin/io/element/android/libraries/eventformatter/api/RoomLastMessageFormatter.kt

@@ -9,6 +9,6 @@ package io.element.android.libraries.eventformatter.api
 
 import io.element.android.libraries.matrix.api.timeline.item.event.EventTimelineItem
 
-interface RoomLastMessageFormatter {
+fun interface RoomLastMessageFormatter {
     fun format(event: EventTimelineItem, isDmRoom: Boolean): CharSequence?
 }