R1:e187519f00a0

When a transaction has no quote ref, render "@user wrote:" properly

Summary:
Fixes T12576. In Javascript, `data.ref` is null, which is getting turned into `/quote/?ref=null`.

The code already handles this case, just not with `ref=null` happening in JS:

https://secure.phabricator.com/source/phabricator/browse/master/src/applications/transactions/controller/PhabricatorApplicationTransactionCommentQuoteController.php;b54adc6161c205e146fabb801ca53a44d94da444$47-52

Test Plan:
{F4913862}

- Also quoted a…