Add glossary tooltips

[Tschakki]

Description

Add automatic tooltips for glossary terms.

Motivation

Having glossary term automatically linked with tool tips would decrease the effort of maintaining the links, and also it would no break the readers flow, because they can view the explanation of the term on the same page.

Additional information

Try: https://gitlab.com/djencks/asciidoctor-glossary

[Tschakki]

Conclusion: The current extension is kind of cumbersome, and it doesn't recognize all existing glossary terms reliably. Therefore we cannot use it in the docs.

We should probably wait until glossaries are officialy supported by Antora.
See: https://gitlab.com/antora/antora/-/issues/928