private void deleteTrackedBranchInBackground() {
    GitBrancher brancher = GitBrancher.getInstance(myProject);
    MultiMap<String, GitRepository> grouped = groupTrackedBranchesByName();
    for (String remoteBranch : grouped.keySet()) {
      brancher.deleteRemoteBranch(remoteBranch, new ArrayList<>(grouped.get(remoteBranch)));
    }
  }
private void deleteTrackedBranchInBackground()