refactor: hide git repo path details from more packages (#38601)

Remove `RepoPath` from "models/repo" package, remove `UserPath` from
"models/user" package, use `WithRepo` for more places, fine tune tests.

models/user/user.go

@@ -13,7 +13,6 @@ import (
 	"mime"
 	"net/mail"
 	"net/url"
-	"path/filepath"
 	"regexp"
 	"strconv"
 	"strings"
@@ -993,12 +992,6 @@ func GetInactiveUsers(ctx context.Context, olderThan time.Duration) ([]*User, er
 		Find(&users)
 }
 
-// UserPath returns the path absolute path of user repositories.
-// FIXME: it should be in "git/gitrepo" package
-func UserPath(userName string) string { //revive:disable-line:exported
-	return filepath.Join(setting.RepoRootPath, filepath.Clean(strings.ToLower(userName)))
-}
-
 // GetUserByID returns the user object by given ID if exists.
 func GetUserByID(ctx context.Context, id int64) (*User, error) {
 	u := new(User)