[Migration tooling] Inline admonition

[bmorelli25]

Summary

You can find an example of an inline admonition in this page:

Data set quality | Elastic Observability [8.17] | Elastic

The text [beta] on top of the page is an inline admonition. If you have over it, you will see a tooltip-style box. There is no equivalent functionality in MyST, so for now we are converting it an admonition of type ‘important'.

```{admonition} <title>
:class: important
<text>
```

To do

• Add support for context-specific admonitions #94 and Add support for page-level metadata #95 will add support for beta/preview callouts to V3
• After these hit, determine a new mapping from asciidoc to v3 for inline admonitions
• Determine which inline admonitions exist outside of the context of versioning and also need to be added

[Mpdreamz]

I don't think we should support this for reasons mentioned here: #94 (comment)

[bmorelli25]

This decision to be validated during migration. Added as an open question to #160.