[ZEUS-4591] Fix video playing in background when switching

[artem-y-pamediagroup]

Jira

• ZEUS-4591
• part of the fix for SE-973, SE-1032

Changes

• fixed removal of action handler targets from MPRemoteCommandCenter, which were capturing an instance of the player
• got rid of the reference to SwiftUI view in the BitmovinPlayerPlugin, used a weak reference to the player itself, in order to make the lifecycle of SwiftUI view and its dependencies predictable
• for this, added a new init for the BitMovinPlayerView to enable passing the player from outside of the view
• added creation and assignment of the uiConfig into the setup method of the plugin, so when the player is created outside it's also set up properly
• inside PlaybackUIView, put the state updates onto the main queue