Invalid links in `template_value` docs

## How can Bevy's documentation be improved?

[`template_value`](https://dev-docs.bevy.org/bevy_scene/scene/fn.template_value.html) uses links for its generic parameter which is displayed like this:

Open the linked template_value API documentation and inspect how the generic parameter links are rendered. Trace the documentation source or generation entry point for this function; the work is done when the displayed generic-parameter links resolve to valid destinations.

Written by the indexing model from the issue text.