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Enough users have complained about the bug label not being applied instead. If there is no label applied
this won't be complained about so often.

For now, it only adds a link to the Discord server.

Co-authored-by: Marc Cornellà <marc.cornella@live.com>
Co-authored-by: Bartek Pacia <barpac02@gmail.com>

Closes #8471

People sometimes use the bug report template for things that are support.
Maintainers will confirm whether it's a bug with the appropriate label.

This commit adds the following issue categories:
- Bug report
- Feature request
- Support