Some small dashboard tweaks:
- Remove margin-bottom from divider so first item does not appear to
have un-equal margins
- Restore previous icon color
- Add slight margin-right to icon
Before:
<img width="783" alt="Screenshot 2023-08-31 at 00 10 28"
src="b75f70d7-8704-4afb-866d-fea0484c52d4">
After:
<img width="783" alt="Screenshot 2023-08-31 at 00 10 08"
src="50ed0c47-6f7c-449e-a054-13091369d43f">
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Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>
Replace #26761
It's better to keep children elements simple, and let parent containers
layout the necessary padding/margin.
The old `not(:last-child)` and `.flex-item + .flex-item` are not easy to
maintain (for example, what if the developer would like to use a "tiny
height" item?)
The old approach also makes some UI look strange because the first item
doesn't have proper padding-top.
In this PR, we just simply use `.flex-item { padding: ... }`:
* Developers could manually set the item height they want easily
* It's easier to make it work with various containers -- with padding
(`ui segment`) and without padding (`div`)
And added more samples/examples.

Co-authored-by: Giteabot <teabot@gitea.io>
Fix#26617
1. Separate the "flex-list" examples into a dedicated template, and add some more examples
2. Use `flex-basis` instead of `flex-shrink` for `flex-item-trailing`, to avoid wrapping the texts too aggressively
3. Some `flex-wrap: wrap;` are removed
This PR introduces a new UI element type for Gitea called `flex-item`.
It consists of a horizontal card with a leading, main and trailing part:

The idea behind it is that in Gitea UI, we have many cases where we use
this kind of layout, but it is achieved in many different ways:
- grid layout
- `.ui.list` with additional hacky flexbox
- `.ui.key.list` - looks to me like a style set originally created for
ssh/gpg key list, was used in many other places
- `.issue.list` - created for issue cards, used in many other places
- ...
This new style is based on `.issue.list`, specifically the refactoring
of it done in #25750.
In this PR, the new element is introduced and lots of templates are
being refactored to use that style. This allows to remove a lot of
page-specific css, makes many of the elements responsive or simply
provides a cleaner/better-looking way to present information.
A devtest section with the new style is also available.
<details>
<summary>Screenshots (left: before, right: after)</summary>



















</details>
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Co-authored-by: Giteabot <teabot@gitea.io>