Follow #32460
Now the code could be much clearer than before and easier to maintain. A
lot of legacy code is removed.
Manually tested.
This PR is large enough, that fine tunes could be deferred to the future if
there is no bug found or design problem.
Screenshots:
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Fix#32453
Major changes:
* revert the `<div class="divider"></div>` in
`templates/repo/issue/branch_selector_field.tmpl` (it was removed by
mistake in ##32444)
* remove incorrect `<div class="inline field">` in
`templates/repo/issue/sidebar/allow_maintainer_edit.tmpl`
* use `gt-ellipsis` to replace the "title" class in the dependency list,
then `.repository .issue-content-right .ui.list .title` could be removed
* remove the "relaxed" from dependency list, then there is no padding,
then `.repository .issue-content-right .ui.list .dependency` could be
removed (`white-space` doesn't have effect either because there is
`gt-ellipsis`)
* remove dead code `.repository .issue-content-right #deadlineForm input
`
The fixed UI should be the same as before.
Kerwin Bryant