Fix issue #2114; Changed network_home_url() to home_url() to avoid wr…

[floek]

Changed network_home_url() to home_url().

Issue: #2114

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Description

Changed network_home_url() to home_url() to avoid wrong return url in multisite setup.

Steps to Test

1. Setup multisite network, woocommerce on sub-page
2. Purchase an item and pay with PayPal, use redirects to paypal page.
3. After payment, the redirect back to the page hits the multisite main page and not the sub-page.

Documentation

• This PR needs documentation (has the "Documentation" label).

Changelog Entry

Avoid wrong return url in multisite setup.

Closes #2114 .

[InpsydeNiklas]

Thanks for the PR! Updated tests were merged with #2157