Events from Gancio now show up in Phanpy with unwanted HTML tags

### Site

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### Version

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### Instance

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### Browser

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### Bug description

The description contains HTML tags which are not stripped, and also not rendered.

At some point recently in Gancio's development, the event description was added to new event's as they are sent out to the Fediverse. Gancio's dev is trying to follow the standards for events in the Fediverse, which may be a space that has seen development. Mastodon 4.3.6 renders the event description correctly, as just text (I assume the tags are stripped out somewhere). Phanpy is not stripping out the included HTML tags.

Here is a related issue for Gancio: https://framagit.org/les/gancio/-/issues/504
Another related Gancio issue: https://framagit.org/les/gancio/-/issues/321
A related Mastodon issue: https://github.com/mastodon/mastodon/issues/28455

### To reproduce

- Tested on version 2024.09.18.30ce4a9c
- Follow a [Gancio](https://gancio.org/) calendar 1.22.0+
- See a new event in your feed, including event description

### Expected behavior

You see the new Gancio event in your Phanpy feed. The description is normal text. This is how I see in Mastodon v4.3.6 web client:

This is the current behavior in Phanpy:

### Other

_No response_