Use ErrInvalidArgument in packages (#22268)

Related to
https://github.com/go-gitea/gitea/pull/22262#discussion_r1059010774

Signed-off-by: Andrew Thornton <art27@cantab.net>
Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>
Co-authored-by: zeripath <art27@cantab.net>
Co-authored-by: Lauris BH <lauris@nix.lv>

models/packages/package_file.go

@@ -5,13 +5,13 @@ package packages
 
 import (
 	"context"
-	"errors"
 	"strconv"
 	"strings"
 	"time"
 
 	"code.gitea.io/gitea/models/db"
 	"code.gitea.io/gitea/modules/timeutil"
+	"code.gitea.io/gitea/modules/util"
 
 	"xorm.io/builder"
 )
@@ -22,9 +22,9 @@ func init() {
 
 var (
 	// ErrDuplicatePackageFile indicates a duplicated package file error
-	ErrDuplicatePackageFile = errors.New("Package file does exist already")
+	ErrDuplicatePackageFile = util.NewAlreadyExistErrorf("package file already exists")
 	// ErrPackageFileNotExist indicates a package file not exist error
-	ErrPackageFileNotExist = errors.New("Package file does not exist")
+	ErrPackageFileNotExist = util.NewNotExistErrorf("package file does not exist")
 )
 
 // EmptyFileKey is a named constant for an empty file key