NFC code cleanup for AuthNet, Paypal, PaypalPro IPNs

[mattwire]

Overview

This cleans up the code for AuthNet, Paypal and PaypalPro IPNS but does not make any functional changes. A follow-up PR (#12387) builds on this and fixes recurring IPNs for PayPal.

Before

• Hardcoded contribution_status IDs.
• Generic error messages with no context.

After

• contribution_status IDs all use pseudoconstants so IPNs will not break if contribution_status option group is different.
• Error messages specify what type of IPN and provide context (eg. transaction ID) to make debugging much easier.

[civibot]

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[eileenmcnaughton]

@mattwire I looked through these changes and they seem good and I think test coverage is adequate here.

My own issue is the vision with handling 'log' - I see a change to

Civi::log()->debug('PayPalProIPN: Could not find txn_type in input request.');

My understanding is that this is pseudonym for the existing function.

However, elsewhere we use this

$log = new CRM_Utils_SystemLogger();
$log->alert('payment_notification processor_name=PayPal', $_REQUEST);

to log to the system_log table. I wonder if we should be using the system log table throughout?

This comment is non blocking & we should discuss with Tim if we want to change