Woocommerce Group Coupons v2.18.0

* Update - WordPress 6.9 compatible.
* Update - WooCommerce 10.4 compatible.
* Dev - CSS adjustments adapt to long coupon codes and text that would overflow outside coupon container.
* Dev - Added missing translators comments.
* Dev - Corrected wrong language domain on a translatable string.
* Dev - Added missing language domain on some translatable strings.
* Update - Updated the translation template.
* Update - Updated the included translations.
* Dev - Updated a deprecated parameter types in function calls.
* Dev - Validation hints for PluginCheck.Security.DirectDB.UnescapedDBParameter.
* Dev - Validation hints for WordPress.DB.DirectDatabaseQuery.DirectQuery.
* Dev - Validation hints for WordPress.DB.DirectDatabaseQuery.NoCaching.
* Dev - Validation hints for WordPress.NamingConventions.PrefixAllGlobals.NonPrefixedHooknameFound.
* Dev - Validation hints for WordPress.NamingConventions.PrefixAllGlobals.NonPrefixedVariableFound.
* Dev - Validation hints for WordPress.PHP.DevelopmentFunctions.error_log_error_log.
* Dev - Validation hints for WordPress.Security.NonceVerification.Missing.
* Dev - Validation hints for WordPress.Security.NonceVerification.Recommended.
* Dev - Validation hints for WordPress.Security.ValidatedSanitizedInput.MissingUnslash.
* Dev - Check presence of potentially undefined request parameters.
* Dev - Added checks for presence and sanitation of server environment information used.