1. There is already `gt-ac`, so no need to introduce `flex-item-center`
2. The `flex-item-baseline` and `.flex-item-icon svg { margin-top: 1px
}` seem to be a tricky patch, they don't resolve the root problem, and
still cause misalignment in some cases.
* The root problem is: the "icon" needs to align with the sibling
"title"
* So, make the "icon" and the "title" both have the same height
3. `flex-text-inline` could only be used if the element is really
"inline", otherwise its `vertical-align` would make the box size change.
In most cases, `flex-text-block` is good enough.
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Co-authored-by: silverwind <me@silverwind.io>
Co-authored-by: Giteabot <teabot@gitea.io>