Reaction highlights (#1145)

* Highlight own reactions

- Highlight own reactions on timeline and improve style.
- Highlight reactions on message bottom sheet only when it our own.

* Improve overlay background colours

* pin to new sdk version

* Remove the red used for debug.

* Fix padding, overlap and only display count if > 1.

- Fix reaction padding and overlap of reaction and bubble.
- Only display count if greater than 1.
- Return EmptyView for TimelineDeliveryStatus.cancelled.

* Fix colors as per design recommendations.

* Add Snapshot tests for reactions and documentation.

- Add UITests for the timeline including reactions.
- Add the reference snapshots.
- Add documentation on how to run snapshot tests and update the reference snapshots.

* Fix Package.resolved

ElementX/Sources/Screens/RoomScreen/View/Style/TimelineItemBubbledStylerView.swift

@@ -86,9 +86,8 @@ struct TimelineItemBubbledStylerView<Content: View>: View {
     }
     
     private var messageBubbleWithReactions: some View {
-        // Figma has a spacing of -4 but it doesn't take into account
-        // the centre aligned stroke width so we use -5 here
-        VStack(alignment: alignment, spacing: -5) {
+        // Figma overlaps reactions by 3
+        VStack(alignment: alignment, spacing: -3) {
             messageBubble
                 .accessibilityElement(children: .combine)