amp-autocomplete example page for email has confusing title

## 🐛 Bug Report

### Current behavior
The page at https://amp.dev/documentation/examples/components/amp-autocomplete-email/?format=email has a title of `Example: `, which is confusing because the actual name of the component is just ``. `amp-autocomplete-email` is also referenced a few times later in the page.

Please also provide:
- Page link: https://amp.dev/documentation/examples/components/amp-autocomplete-email/?format=email

### Expected behavior/code
The title of the page should be `Example: `, and there should be no references to `amp-autocomplete-email` but `amp-autocomplete`.

/to @caroqliu