Fix incorrect setting of the SameSite cookie param

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Co-authored-by: Denis Kopylov <dkopylov@magenius.team>

Author: ihor-sviziev

app/code/Magento/PageCache/view/frontend/web/js/form-key-provider.js

@@ -17,15 +17,15 @@ define(function () {
         function setFormKeyCookie(value) {
             var expires,
                 secure,
-                samesite,
                 date = new Date(),
                 cookiesConfig = window.cookiesConfig || {},
                 isSecure = !!cookiesConfig.secure;
+                samesite = cookiesConfig.samesite || 'lax';
 
             date.setTime(date.getTime() + 86400000);
             expires = '; expires=' + date.toUTCString();
             secure = isSecure ? '; secure' : '';
-            samesite = '; samesite=' + (cookiesConfig.samesite ? cookiesConfig.samesite : 'lax');
+            samesite = '; samesite=' + samesite;
 
             document.cookie = 'form_key=' + (value || '') + expires + secure + '; path=/' + samesite;
         }