the search debouncing doesn't need to block the background thread before the first search query was executed

deltachat-ios/ViewModel/ChatListViewModel.swift

@@ -355,7 +355,6 @@ extension ChatListViewModel: UISearchResultsUpdating {
         } else {
             inBgSearch = true
             DispatchQueue.global(qos: .userInteractive).async { [weak self] in
-                usleep(100000)
                 self?.needsAnotherBgSearch = false
                 self?.filterContentForSearchText(self?.searchText ?? "")