fix: do not list pull requests

pkg/invoice/invoice.go

@@ -20,6 +20,7 @@ func (s *Service) Generate(creditor model.Entity, deptor *model.Entity, rate flo
 			repo.Repo,
 			gitea.ListIssueOption{
 				ListOptions: gitea.ListOptions{Page: 0, PageSize: 99999},
+				Type:        gitea.IssueTypeIssue,
 				Since:       config.Since,
 				Before:      config.Before,
 				State:       config.IssueState,