Redirect from PayPal standard settings to PPEC settings is broken

[mattallan]

With PPEC enabled, when a user visits the PayPal standard settings they should be redirected to the PPEC settings page - this should be happening inside the maybe_redirect_to_ppec_settings() function.

This function is doing two things wrong:

• we're looking for out-of-date GET params - &section=wc_gateway_paypal is no longer used, instead, we should be looking for &section=paypal
• we're redirecting the customer to a blank page &section=wc_gateway_ppec_with_paypal doesn't exist on WC > 3.0, we should be redirecting to &section=ppec_paypal

[james-allan]

I actually saw this function recently too and questioned what it's intended to do. When the user visits the PayPal settings, we redirect them to the PPEC page.

Essentially with PPEC enabled we override the core PayPal settings? As part of this issue we should investigate if that's still the intention.