refactor: ForumChannel extends Channel

[DaStormer]

Please describe the changes this PR makes and why it should be merged:

Status

• [ ] Code changes have been tested.

Semantic versioning classification:

• [ ] This PR changes the library's interface (methods or parameters added)
• [ ] This PR includes breaking changes (methods removed or renamed, parameters moved or removed)
• [ ] This PR only includes non-code changes, like changes to documentation, README, etc.

[changeset-bot[bot]]

⚠️ No Changeset found

Latest commit: e03813b7525d81b7b37622c1fd8aea90a743b9bc

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