build(deps): Bump gatsby-plugin-feed from 5.14.0 to 5.15.0

Bumps [gatsby-plugin-feed](https://github.com/gatsbyjs/gatsby/tree/HEAD/packages/gatsby-plugin-feed) from 5.14.0 to 5.15.0.
- [Release notes](https://github.com/gatsbyjs/gatsby/releases)
- [Changelog](https://github.com/gatsbyjs/gatsby/blob/master/packages/gatsby-plugin-feed/CHANGELOG.md)
- [Commits](https://github.com/gatsbyjs/gatsby/commits/gatsby-plugin-feed@5.15.0/packages/gatsby-plugin-feed)

---
updated-dependencies:
- dependency-name: gatsby-plugin-feed
  dependency-version: 5.15.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

package-lock.json

@@ -23,7 +23,7 @@
     "axios": "^1.11.0",
     "decode-uri-component": "^0.4.1",
     "gatsby": "^5.14.6",
-    "gatsby-plugin-feed": "^5.14.0",
+    "gatsby-plugin-feed": "^5.15.0",
     "gatsby-plugin-layout": "^4.14.0",
     "gatsby-plugin-matomo": "^0.17.0",
     "gatsby-plugin-sass": "^6.14.0",