Title can be empty when creating tag only (#23917)

Fixes #23809

Make the title not required. If the title is empty when creating release
(not tag), an error message will be displayed.

![image](https://user-images.githubusercontent.com/15528715/229761056-c52e338b-5f25-4d7d-bb44-2cb0304abcee.png)

options/locale/locale_en-US.ini

@@ -2308,6 +2308,7 @@ release.tag_helper = Choose an existing tag or create a new tag.
 release.tag_helper_new = New tag. This tag will be created from the target.
 release.tag_helper_existing = Existing tag.
 release.title = Title
+release.title_empty = Title cannot be empty.
 release.content = Content
 release.prerelease_desc = Mark as Pre-Release
 release.prerelease_helper = Mark this release unsuitable for production use.

routers/web/repo/release.go

@@ -360,6 +360,12 @@ func NewReleasePost(ctx *context.Context) {
 		return
 	}
 
+	// Title of release cannot be empty
+	if len(form.TagOnly) == 0 && len(form.Title) == 0 {
+		ctx.RenderWithErr(ctx.Tr("repo.release.title_empty"), tplReleaseNew, &form)
+		return
+	}
+
 	var attachmentUUIDs []string
 	if setting.Attachment.Enabled {
 		attachmentUUIDs = form.Files

services/forms/repo_form.go

@@ -693,7 +693,7 @@ type UpdateAllowEditsForm struct {
 type NewReleaseForm struct {
 	TagName    string `binding:"Required;GitRefName;MaxSize(255)"`
 	Target     string `form:"tag_target" binding:"Required;MaxSize(255)"`
-	Title      string `binding:"Required;MaxSize(255)"`
+	Title      string `binding:"MaxSize(255)"`
 	Content    string
 	Draft      string
 	TagOnly    string

templates/repo/release/new.tmpl

@@ -47,7 +47,7 @@
 			<div class="eleven wide column">
 				<div class="field {{if .Err_Title}}error{{end}}">
 					<label>{{.locale.Tr "repo.release.title"}}</label>
-					<input name="title" placeholder="{{.locale.Tr "repo.release.title"}}" value="{{.title}}" autofocus required maxlength="255">
+					<input name="title" placeholder="{{.locale.Tr "repo.release.title"}}" value="{{.title}}" autofocus maxlength="255">
 				</div>
 				<div class="field">
 					<label>{{.locale.Tr "repo.release.content"}}</label>