Change 'tiger' to 'lion'

- [ ] Use `git pull` the latest changes from GitHub.
- [ ] Open a branch on this issue
- [ ] Open the poem and change `tiger` to `lion`
- [ ] use `git` CLI to `add`, `commit` and `push`

Try to run to get an idea of what is happening.

```shell
git log --oneline --all --graph
```

Or use the GitLens extension!