add the "Landed in <commit hash>..<commit hash>" comment if you added

multiple commits.

### Troubleshooting

Sometimes, when running `git push upstream master`, you may get an error message

like this:

```console

To https://github.com/nodejs/node

! [rejected] master -> master (fetch first)

error: failed to push some refs to 'https://github.com/nodejs/node'

hint: Updates were rejected because the remote contains work that you do

hint: not have locally. This is usually caused by another repository pushing

hint: to the same ref. You may want to first integrate the remote changes

hint: (e.g., 'git pull ...') before pushing again.

hint: See the 'Note about fast-forwards' in 'git push --help' for details.

```

That means a commit has landed since your last rebase against `upstream/master`.

To fix this, fetch, rebase, run the tests again (to make sure no interactions

between your changes and the new changes cause any problems), and push again:

```sh

git fetch upstream

git rebase upstream/master

make -j4 test

git push upstream master

```

### I Just Made a Mistake

* Ping a CTC member.