Fix nil error when sorting room aliases

Under some circumstances, the array of canonical aliases may contain
nil entries, which causes the sort to fail. This solution simply removes
those nil entries before sorting.

Author: thelibrarian

lib/matrix_sdk/room.rb

@@ -981,7 +981,7 @@ def handle_room_canonical_alias(event)
       data = tinycache_adapter.read(:aliases) || []
       data << canonical_alias
       data += event.dig(*%i[content alt_aliases]) || []
-      tinycache_adapter.write(:aliases, data.uniq.sort)
+      tinycache_adapter.write(:aliases, data.compact.uniq.sort)
     end
 
     def room_handlers?