Special characters sent via URL for the page are causing an internal server error.

Steps to Reproduce the Issue

1) Install the Google Programmable Search JSON API and configure it accordingly.

2) In the URL, use the following format: search/google?keys=search&page=%2527.
This will result in the following error:
TypeError: Unsupported operand types: string * string in Drupal\\google_json_api\\Plugin\\Search\\GoogleJsonApiSearch->execute() (line 164 of modules/contrib/google_json_api/src/Plugin/Search/GoogleJsonApiSearch.php).

If you remove the special character in the page parameter (in this case, %), the functionality will work as expected.