Fix Session gets expired using AJAX with Session

[crustamet]

Fix session class setcookie not getting renewed when using ajax and put expire date in the past.

Each pull request should address a single issue and have a meaningful title.

Description
Explain what you have changed, and why.

Checklist:

• Securely signed commits
• Component(s) with PHPdocs
• Unit testing, with >80% coverage
• User guide updated
• Conforms to style guide

---------Remove from here down in your description----------

Notes

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[michalsn]

Thank you for your first PR!

I will merge this in this shape since from what I understand these changes were made via the web interface. Not sure if there is an option to rebase.

I will add more tests for this in next PR.