DevHub: Add support for inline @see and @link tags in return descriptions

[DrewAPicture]

Currently, return descriptions are late-escaped on output with esc_html() which doesn't allow for inline @see and @link tags to display as expected. The links are parsed, but the respective {@link and } parts are still present on output.

I spoke with @coffee2code about applying the make_doclink_clickable() method on return descriptions instead and he agrees that should be fine.

As we move more and more toward adding extended documentation to references via the Explanations module, linking parameter and return descriptions to external resources is becoming more common.

[drewapicture]

In 1915:

DevHub: Add support for inline @see and @link tags to be rendered in return descriptions.

Fixes #1251.