Draft: Pick a name for the Persistent Dismissible Callout Alerts

We should pick a name for the feature we currently call Callouts, and the components that implement it's behaviour. So far we have:

• "Callouts" used in the docs
• "dismissible", introduced in !205593 (merged)
• "persistent" used in the JS files

Original thread:

The following discussion from !205593 (merged) should be addressed:

• @kpalchyk started a discussion: (+3 comments)

  thought (non-blocking): not related to current MR. We seem have a misalignment in naming 😞

  We call this thing callouts in docs, sometimes we call it dismissible, in js they are persistent.

  Maybe those are aspects of the same thing. I'm just voicing that this naming could be confusing...