Should look exactly like before for normal dividers. "Horizontal" ones
look better because they no longer use image backgrounds.
<img width="917" alt="Screenshot 2023-06-27 at 19 07 56"
src="d97d8dec-6859-44a8-85ba-e4549b4dd9df">
<img width="914" alt="Screenshot 2023-06-27 at 19 05 58"
src="8bf98544-2d82-4ebf-ac68-d6dc237bd6b2">
<img width="1246" alt="Screenshot 2023-06-27 at 19 00 42"
src="36a6bb21-6029-4f53-8bee-535f55c66fed">
<img width="344" alt="Screenshot 2023-06-27 at 18 58 15"
src="a9e70aee-8e6b-4ea1-9e93-19c9f96aec6e">
<img width="823" alt="Screenshot 2023-06-27 at 18 56 22"
src="e7a497cd-f262-4683-8872-23c3c8cce32f">
<img width="330" alt="Screenshot 2023-06-27 at 19 21 11"
src="42f24149-a655-4c7e-bd26-8ab52db6446b">
Address
https://github.com/go-gitea/gitea/pull/25163#issuecomment-1599207916
Remove the unused "icon-button".
And fix the layout:
Without the dropdown icon:
```
{{svg "gitea-whitespace"}}
```

With the dropdown icon:
```
{{svg "gitea-whitespace" 16 "gt-mr-3"}}
{{svg "octicon-triangle-down" 14 "dropdown icon"}}
```

This refactors the `shared/datetime/short|long|full` templates into a
template helper function, which allows us to render absolute date times
within translatable phrases.
- Follows #23988
- The first attempt was in #24055
- This should help #22664
Changes:
1. Added the `DateTime` template helper that replaces the
`shared/datetime/short|long|full` templates
2. Used find-and-replace with varying regexes to replace the templates
from step 1 (for example, `\{\{template "shared/datetime/(\S+) \(dict
"Datetime" ([^"]+) "Fallback" ([^\)]+\)?) ?\)?\}\}` -> `{{DateTime "$1
$2 $3}}`)
3. Used the new `DateTime` helper in the issue due date timestamp
rendering
# Before

# After

---------
Signed-off-by: Yarden Shoham <git@yardenshoham.com>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>