Automatic generation of release notes (#35977)

Similar to GitHub, release notes can now be generated automatically.
The generator is server-side and gathers the merged PRs and contributors
and returns the corresponding Markdown text.

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Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

routers/web/web.go

@@ -1403,6 +1403,7 @@ func registerWebRoutes(m *web.Router) {
 		m.Group("/releases", func() {
 			m.Get("/new", repo.NewRelease)
 			m.Post("/new", web.Bind(forms.NewReleaseForm{}), repo.NewReleasePost)
+			m.Post("/generate-notes", web.Bind(forms.GenerateReleaseNotesForm{}), repo.GenerateReleaseNotes)
 			m.Post("/delete", repo.DeleteRelease)
 			m.Post("/attachments", repo.UploadReleaseAttachment)
 			m.Post("/attachments/remove", repo.DeleteAttachment)