The "legacy" name for this trigger has the wrong eventsub topic name

[BarryCarlyon]

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Problem/Feature

Please include a description of the problem or feature this PR is addressing.

Description of Changes:

barrycarlyon@Robyn ~ % twitch event trigger unsubscribe
{"subscription":{"id":"fd1f9269-148c-fc06-4c2f-996580207d91","status":"enabled","type":"channel.unsubscribe","version":"1","condition":{"broadcaster_user_id":"8594094"},"transport":{"method":"webhook","callback":"null"},"created_at":"2021-12-14T14:29:25.352469Z","cost":0},"event":{"user_id":"57434785","user_login":"testFromUser","user_name":"testFromUser","broadcaster_user_id":"8594094","broadcaster_user_login":"testBroadcaster","broadcaster_user_name":"testBroadcaster","tier":"1000","is_gift":false}}

fixed to

barrycarlyon@Robyn ~ % twitch event trigger unsubscribe
{"subscription":{"id":"9466cce5-dd5b-4af7-6178-0ffc3f7db3e8","status":"enabled","type":"channel.subscription.end","version":"1","condition":{"broadcaster_user_id":"33893692"},"transport":{"method":"webhook","callback":"null"},"created_at":"2021-12-14T14:30:37.098126Z","cost":0},"event":{"user_id":"37902996","user_login":"testFromUser","user_name":"testFromUser","broadcaster_user_id":"33893692","broadcaster_user_login":"testBroadcaster","broadcaster_user_name":"testBroadcaster","tier":"1000","is_gift":false}}

Checklist

• My code follows the Contribution Guide
• I have self-reviewed the changes being requested
• I have made comments on pieces of code that may be difficult to understand for other editors
• I have updated the documentation (if applicable)