[Feature Request]: Change how the `title` in the `head` is defined

### Prerequisites

- [x] I have searched existing issues to ensure this feature hasn't already been requested
- [x] I have tested using the latest version of docs-builder

### What problem are you trying to solve?

We've noticed that some pages are being marked as duplicates by search engines even when they are not duplicates. The SEO team found that some pages have the same `title` in the `head` that in the AsciiDoc build system had different titles. For example, the `title` on both of these pages are the same (`Configure Kerberos | Beats`):

* https://www.elastic.co/docs/reference/beats/filebeat/configuration-kerberos
* https://www.elastic.co/docs/reference/beats/metricbeat/configuration-kerberos

I _think_ the second part of the `title`, `Beats`, is coming from the title of the first page in the docset based on [this](https://github.com/elastic/docs-builder/blob/main/src/Elastic.Markdown/Page/Index.cshtml#L17) and this:

### Proposed Solution

I'm not sure _how_ we should define the `title` instead, but in the example above using `Filebeat` and `Metricbeat` instead of `Beats` would help make the `title`s unique. Happy to brainstorm other options!

### Examples and Research

_No response_

### Alternative Solutions

_No response_

### Additional Context

_No response_

### How important is this feature to you?

Important