Remove handbook from document title.

[StevenDufresne]

Two of the most well visited pages on developer.wp.org are:

• https://developer.wordpress.org/advanced-administration/before-install/howto-install/
• https://developer.wordpress.org/advanced-administration/debug/debug-wordpress/

Most of the traffic comes from search results.

We currently append the handbook name to the title in the format {post title} - {handbook} name. In my opinon, the handbook title is irrelevant to users and makes the result less appealing.

(the excerpt also need help)

Here's how they appear in Google search results:

cc @jonoalderson

[jonoalderson]

If we remove that stem, can we be confident that there aren't / won't be a ton of other pages with the same title? Nervous about accidental large-scale duplication of titles. 🤔

[StevenDufresne]

Good point. I'll pull some data as a next step.