Order Details Paid By Customer section hidden if no date_paid returned

[astralbodies]

To match Core behavior, let's update the app to show/hide the "Paid by customer" section in order details based on there being a date paid or not.

Core: https://github.com/woocommerce/woocommerce/pull/25504#discussion_r375455622

Verify payment details show up properly when using the "Cash on delivery" option.

cc: @LevinMedia

iOS issue: https://github.com/woocommerce/woocommerce-ios/issues/1827

[anitaa1990]

@astralbodies is this still a valid issue? I see that if the order is a cash on delivery order, then the app displays the Awaiting payment text.

[astralbodies]

I'll close it for now; I bet we addressed it and didn't close the issue at the time. 😄