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"}}
```
