icon request: Gitea

### Describe the Icon

Ionicons already includes icons for GitLab, GitHub, and Bitbucket, which is great.
However, it would be helpful to also include an icon for [Gitea](https://gitea.io/), which is also a popular Git service.

Adding a Gitea icon would make Ionicons more complete and useful for developers who work with Gitea.

### Links to Examples

Official SVG: https://github.com/go-gitea/gitea/blob/main/public/assets/img/gitea.svg
Simple Icons: https://github.com/simple-icons/simple-icons/blob/develop/icons/gitea.svg

### Additional Information

_No response_

Start by comparing the linked official Gitea SVG and Simple Icons version with the existing GitLab, GitHub, and Bitbucket icons in the repository. Determine how those icons are represented and included, then add the Gitea icon consistently and verify that it appears in the generated icon set.

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