Add missing database transaction for new issue (#29490) (#29607)

When creating an issue, inserting issue, assign users and set project
should be in the same transaction.

Backport #29490

routers/api/v1/repo/issue.go

@@ -707,7 +707,7 @@ func CreateIssue(ctx *context.APIContext) {
 		form.Labels = make([]int64, 0)
 	}
 
-	if err := issue_service.NewIssue(ctx, ctx.Repo.Repository, issue, form.Labels, nil, assigneeIDs); err != nil {
+	if err := issue_service.NewIssue(ctx, ctx.Repo.Repository, issue, form.Labels, nil, assigneeIDs, 0); err != nil {
 		if repo_model.IsErrUserDoesNotHaveAccessToRepo(err) {
 			ctx.Error(http.StatusBadRequest, "UserDoesNotHaveAccessToRepo", err)
 			return