Add moneybag emoji in h1bbc issue thread after paying bounty

Problem Statement

There's currently an undocumented workflow where we indicate bounty award payment status by adding a "paid" comment to the relevant h1bbc issue thread. This is helpful because it allows one to see which bounties have yet to be paid.

Why is this a problem?

1. It's noisy. Each time a "paid" comment is added to a bug bounty council issue, everyone on AppSec team gets an email update about it. We can't tell which bounty has been paid by looking at the email thread, we just get an update that someone commented "paid" about something - not particularly helpful.
2. Indicating award payout status in bug bounty council issues is not documented in our runbooks.

What is the change?

Adds final step to add 💰 emoji in bug bounty council thread to indicate bounty has been paid to our h1 runbook.

Why is this change being made?

Notification-free way to indicate whether a particular bug bounty has been paid.

Author Checklist

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