Replace all instances of fmt.Errorf(%v) with fmt.Errorf(%w) (#21551)

Found using
`find . -type f -name '*.go' -print -exec vim {} -c
':%s/fmt\.Errorf(\(.*\)%v\(.*\)err/fmt.Errorf(\1%w\2err/g' -c ':wq' \;`

Co-authored-by: 6543 <6543@obermui.de>
Co-authored-by: Andrew Thornton <art27@cantab.net>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

models/repo_collaboration.go

@@ -66,7 +66,7 @@ func reconsiderRepoIssuesAssignee(ctx context.Context, repo *repo_model.Reposito
 	if _, err := db.GetEngine(ctx).Where(builder.Eq{"assignee_id": uid}).
 		In("issue_id", builder.Select("id").From("issue").Where(builder.Eq{"repo_id": repo.ID})).
 		Delete(&issues_model.IssueAssignees{}); err != nil {
-		return fmt.Errorf("Could not delete assignee[%d] %v", uid, err)
+		return fmt.Errorf("Could not delete assignee[%d] %w", uid, err)
 	}
 	return nil
 }