WebhookExtraHeaders are custom HTTP headers that Blueink will include when
delivering events to a Webhook. Common uses include attaching a shared secret or
bearer token so your receiver can authenticate the incoming request as originating
from Blueink.

```mdx-code-block
import DocCardList from '@theme/DocCardList';
import {useCurrentSidebarCategory} from '@docusaurus/theme-common';

<DocCardList items={useCurrentSidebarCategory().items}/>
```