Make issue title edit buttons focusable and fix incorrect ajax requests (#22807)

Replace #19922 , which is stale since my last review:
#19922 (review)
and #19922 (comment)

Close #19769

Changes:
1. Use `<button>` instead of `<div>` for buttons
2. Prevent default event handler in `initGlobalButtonClickOnEnter`
3. Fix the incorrect call to `pullrequest_targetbranch_change`
4. Add a slight margin-left to the input element to make UI look better

The logic in repo-issue.js is not ideal, but this PR isn't going to
touch the logic.

This is also an example for future developers to understand how to make
buttons work properly.

### Before


![image](https://user-images.githubusercontent.com/2114189/217262515-ec0462f7-7051-46a5-bfa2-2f6c6a807b7d.png)

### After

* Add a slight margin-left.
* The `Cancel` button is focused.


![image](https://user-images.githubusercontent.com/2114189/217264891-934c9c8d-d190-4866-98b5-666cea57e28d.png)

Co-authored-by: techknowlogick <techknowlogick@gitea.io>

Author: wxiaoguang

templates/repo/issue/view_title.tmpl

@@ -2,20 +2,20 @@
 	<div class="issue-title" id="issue-title-wrapper">
 		{{if and (or .HasIssuesOrPullsWritePermission .IsIssuePoster) (not .Repository.IsArchived)}}
 			<div class="edit-button">
-				<div id="edit-title" class="ui basic secondary not-in-edit button">{{.locale.Tr "repo.issues.edit"}}</div>
+				<button id="edit-title" class="ui basic button secondary not-in-edit">{{.locale.Tr "repo.issues.edit"}}</button>
 			</div>
 		{{end}}
 		<h1>
 			<span id="issue-title">{{RenderIssueTitle $.Context .Issue.Title $.RepoLink $.Repository.ComposeMetas | RenderCodeBlock}}</span>
 			<span class="index">#{{.Issue.Index}}</span>
-			<div id="edit-title-input" class="ui input" style="display: none">
+			<div id="edit-title-input" class="ui input ml-4" style="display: none">
 				<input value="{{.Issue.Title}}" maxlength="255" autocomplete="off">
 			</div>
 		</h1>
 		{{if and (or .HasIssuesOrPullsWritePermission .IsIssuePoster) (not .Repository.IsArchived)}}
 			<div class="edit-buttons">
-				<div id="cancel-edit-title" class="ui basic secondary in-edit button" style="display: none">{{.locale.Tr "repo.issues.cancel"}}</div>
-				<div id="save-edit-title" class="ui primary in-edit button" style="display: none" data-update-url="{{$.RepoLink}}/issues/{{.Issue.Index}}/title" {{if .Issue.IsPull}}data-target-update-url="{{$.RepoLink}}/pull/{{.Issue.Index}}/target_branch"{{end}}>{{.locale.Tr "repo.issues.save"}}</div>
+				<button id="cancel-edit-title" class="ui basic button secondary in-edit" style="display: none">{{.locale.Tr "repo.issues.cancel"}}</button>
+				<button id="save-edit-title" class="ui primary button in-edit" style="display: none" data-update-url="{{$.RepoLink}}/issues/{{.Issue.Index}}/title" {{if .Issue.IsPull}}data-target-update-url="{{$.RepoLink}}/pull/{{.Issue.Index}}/target_branch"{{end}}>{{.locale.Tr "repo.issues.save"}}</button>
 			</div>
 		{{end}}
 	</div>

web_src/js/features/common-global.js

@@ -60,6 +60,7 @@ export function initGlobalButtonClickOnEnter() {
   $(document).on('keypress', '.ui.button', (e) => {
     if (e.keyCode === 13 || e.keyCode === 32) { // enter key or space bar
       $(e.target).trigger('click');
+      e.preventDefault();
     }
   });
 }

web_src/js/features/repo-issue.js

@@ -605,6 +605,7 @@ export function initRepoIssueTitleEdit() {
       const targetBranch = $('#pull-target-branch').data('branch');
       const $branchTarget = $('#branch_target');
       if (targetBranch === $branchTarget.text()) {
+        window.location.reload();
         return false;
       }
       $.post(update_url, {
@@ -617,19 +618,22 @@ export function initRepoIssueTitleEdit() {
       });
     };
 
-    const pullrequest_target_update_url = $(this).data('target-update-url');
+    const pullrequest_target_update_url = $(this).attr('data-target-update-url');
     if ($editInput.val().length === 0 || $editInput.val() === $issueTitle.text()) {
       $editInput.val($issueTitle.text());
       pullrequest_targetbranch_change(pullrequest_target_update_url);
     } else {
-      $.post($(this).data('update-url'), {
+      $.post($(this).attr('data-update-url'), {
         _csrf: csrfToken,
         title: $editInput.val()
       }, (data) => {
         $editInput.val(data.title);
         $issueTitle.text(data.title);
-        pullrequest_targetbranch_change(pullrequest_target_update_url);
-        window.location.reload();
+        if (pullrequest_target_update_url) {
+          pullrequest_targetbranch_change(pullrequest_target_update_url); // it will reload the window
+        } else {
+          window.location.reload();
+        }
       });
     }
     return false;

web_src/less/_base.less

@@ -2316,6 +2316,13 @@ a.ui.label:hover {
 .ui.basic.secondary.buttons .button:active,
 .ui.basic.secondary.button:active {
   color: var(--color-secondary-dark-8) !important;
+  border-color: var(--color-secondary-dark-1) !important;
+}
+
+.ui.basic.secondary.button:focus,
+.ui.basic.secondary.buttons .button:focus {
+  color: var(--color-secondary-dark-8) !important;
+  border-color: var(--color-secondary-dark-3) !important;
 }
 
 .ui.tertiary.button {