Fix diff detail buttons wrapping, use tippy for review box (#23271)

Fix visual regression introduced by
https://github.com/go-gitea/gitea/pull/22986.

Before:
<img width="1277" alt="image"
src="https://user-images.githubusercontent.com/115237/222792814-d70c2173-0c7c-4db2-8839-95be63cdc8ee.png">
<img width="649" alt="image"
src="https://user-images.githubusercontent.com/115237/222792989-9b1f5e12-becd-40cc-b02c-e9f59a8e72a4.png">

After: 
<img width="1274" alt="image"
src="https://user-images.githubusercontent.com/115237/222792769-e7a9702f-4b6a-46c4-9385-da103ed4dff0.png">
<img width="565" alt="image"
src="https://user-images.githubusercontent.com/115237/222793084-6de6482b-11dc-4d38-b514-15884d20e140.png">

templates/repo/diff/box.tmpl

@@ -24,7 +24,7 @@
 					{{svg "octicon-diff" 16 "gt-mr-2"}}{{.locale.Tr "repo.diff.stats_desc" .Diff.NumFiles .Diff.TotalAddition .Diff.TotalDeletion | Str2html}}
 				</div>
 			</div>
-			<div class="diff-detail-actions gt-df gt-ac gt-w-100">
+			<div class="diff-detail-actions gt-df gt-ac">
 				{{if and .PageIsPullFiles $.SignedUserID (not .IsArchived)}}
 					<progress id="viewed-files-summary" class="gt-mr-2" value="{{.Diff.NumViewedFiles}}" max="{{.Diff.NumFiles}}"></progress>
 					<label for="viewed-files-summary" id="viewed-files-summary-label" class="gt-mr-3 gt-f1" data-text-changed-template="{{.locale.Tr "repo.pulls.viewed_files_label"}}">

templates/repo/diff/new_review.tmpl

@@ -4,7 +4,7 @@
 		<span class="ui small label review-comments-counter" data-pending-comment-number="{{.PendingCodeCommentNumber}}">{{.PendingCodeCommentNumber}}</span>
 		{{svg "octicon-triangle-down" 14 "dropdown icon"}}
 	</button>
-	<div class="review-box-panel gt-hidden">
+	<div class="review-box-panel tippy-target">
 		<div class="ui segment">
 			<form class="ui form" action="{{.Link}}/reviews/submit" method="post">
 			{{.CsrfTokenHtml}}