Improve issue history dialog and make poster can delete their own history (#27323)

Fix #27313 (see the comment)

And some UI improvements:

### Before


![image](https://github.com/go-gitea/gitea/assets/2114189/420a314d-8f34-4e30-a557-f41cf4f0d2f2)


![image](https://github.com/go-gitea/gitea/assets/2114189/60ca0be4-b55e-4e65-be73-fd53e0d4fc36)


### After


![image](https://github.com/go-gitea/gitea/assets/2114189/d354f815-5a0c-4e63-8d59-d03ed344dbea)


![image](https://github.com/go-gitea/gitea/assets/2114189/6ef437a4-aa6f-4917-a260-00625ee71e79)


![image](https://github.com/go-gitea/gitea/assets/2114189/9d88a36c-616b-4dc9-8c6b-76adaad8acf6)

1 files changed, 4 insertions, 3 deletions

diff --git a/web_src/js/features/repo-issue-content.js b/web_src/js/features/repo-issue-content.js
index 3ada166c5b..7832641687 100644
--- a/web_src/js/features/repo-issue-content.js
+++ b/web_src/js/features/repo-issue-content.js
@@ -17,14 +17,15 @@ function showContentHistoryDetail(issueBaseUrl, commentId, historyId, itemTitleH
   ${svg('octicon-x', 16, 'close icon inside')}
   <div class="header gt-df gt-ac gt-sb">
     <div>${itemTitleHtml}</div>
-    <div class="ui dropdown dialog-header-options gt-df gt-ac gt-mr-5 gt-hidden">
-      ${i18nTextOptions}${svg('octicon-triangle-down', 14, 'dropdown icon')}
+    <div class="ui dropdown dialog-header-options gt-mr-5 gt-hidden">
+      ${i18nTextOptions}
+      ${svg('octicon-triangle-down', 14, 'dropdown icon')}
       <div class="menu">
         <div class="item red text" data-option-item="delete">${i18nTextDeleteFromHistory}</div>
       </div>
     </div>
   </div>
-  <div class="comment-diff-data gt-text-left gt-p-3 is-loading"></div>
+  <div class="comment-diff-data is-loading"></div>
 </div>`);
   $dialog.appendTo($('body'));
   $dialog.find('.dialog-header-options').dropdown({