Fix incorrect redirection when creating a PR fails (#29537)

This is only a quick fix to make it easier to backport.

After this PR gets merged, I will propose a new PR to fix the FIXME.

<details>

![image](https://github.com/go-gitea/gitea/assets/2114189/98d1d5c4-2e79-4a75-80e9-76fd898986e0)

</details>

options/locale/locale_en-US.ini

@@ -1792,9 +1792,9 @@ pulls.unrelated_histories = Merge Failed: The merge head and base do not share a
 pulls.merge_out_of_date = Merge Failed: Whilst generating the merge, the base was updated. Hint: Try again.
 pulls.head_out_of_date = Merge Failed: Whilst generating the merge, the head was updated. Hint: Try again.
 pulls.has_merged = Failed: The pull request has been merged, you cannot merge again or change the target branch.
-pulls.push_rejected = Merge Failed: The push was rejected. Review the Git Hooks for this repository.
+pulls.push_rejected = Push Failed: The push was rejected. Review the Git Hooks for this repository.
 pulls.push_rejected_summary = Full Rejection Message
-pulls.push_rejected_no_message = Merge Failed: The push was rejected but there was no remote message.<br>Review the Git Hooks for this repository
+pulls.push_rejected_no_message = Push Failed: The push was rejected but there was no remote message. Review the Git Hooks for this repository
 pulls.open_unmerged_pull_exists = `You cannot perform a reopen operation because there is a pending pull request (#%d) with identical properties.`
 pulls.status_checking = Some checks are pending
 pulls.status_checks_success = All checks were successful

routers/web/repo/pull.go

@@ -1501,7 +1501,7 @@ func CompareAndPullRequestPost(ctx *context.Context) {
 				return
 			}
 			ctx.Flash.Error(flashError)
-			ctx.JSONRedirect(pullIssue.Link()) // FIXME: it's unfriendly, and will make the content lost
+			ctx.JSONRedirect(ctx.Link + "?" + ctx.Req.URL.RawQuery) // FIXME: it's unfriendly, and will make the content lost
 			return
 		}
 		ctx.ServerError("NewPullRequest", err)

templates/repo/diff/compare.tmpl

@@ -11,14 +11,6 @@
 			{{ctx.Locale.Tr "action.compare_commits_general"}}
 		{{end}}
 	</h2>
-	{{if .Flash.WarningMsg}}
-		{{/*
-			There's already an importing of alert.tmpl in new_form.tmpl,
-			but only the negative message will be displayed within forms for some reasons, see semantic.css:10659.
-			To avoid repeated negative messages, the importing here if for .Flash.WarningMsg only.
-		*/}}
-		{{template "base/alert" .}}
-	{{end}}
 	{{$BaseCompareName := $.BaseName -}}
 	{{- $HeadCompareName := $.HeadRepo.OwnerName -}}
 	{{- if and (eq $.BaseName $.HeadRepo.OwnerName) (ne $.Repository.Name $.HeadRepo.Name) -}}

templates/repo/issue/new.tmpl

@@ -2,14 +2,6 @@
 <div role="main" aria-label="{{.Title}}" class="page-content repository new issue">
 	{{template "repo/header" .}}
 	<div class="ui container">
-		{{if .Flash.WarningMsg}}
-			{{/*
-			There's already an importing of alert.tmpl in new_form.tmpl,
-			but only the negative message will be displayed within forms for some reasons, see semantic.css:10659.
-			To avoid repeated negative messages, the importing here if for .Flash.WarningMsg only.
-			 */}}
-			{{template "base/alert" .}}
-		{{end}}
 		{{template "repo/issue/new_form" .}}
 	</div>
 </div>

templates/repo/issue/new_form.tmpl

@@ -1,10 +1,8 @@
+{{if .Flash}}
+{{template "base/alert" .}}
+{{end}}
 <form class="issue-content ui comment form form-fetch-action" id="new-issue" action="{{.Link}}" method="post">
 	{{.CsrfTokenHtml}}
-	{{if .Flash}}
-		<div class="sixteen wide column">
-			{{template "base/alert" .}}
-		</div>
-	{{end}}
 	<div class="issue-content-left">
 		<div class="ui comments">
 			<div class="comment">