[feat] download: normalise download url.
If URL is rewritten with .netrc and path contains '//' or '../', like '/repository/files/a%2F..%2Fb/raw?ref=xxx', GitLab raises an error : file_path should be a valid file path.
If URL is rewritten with .netrc and path contains '//' or '../', like '/repository/files/a%2F..%2Fb/raw?ref=xxx', GitLab raises an error : file_path should be a valid file path.