build(deps): bump gatsby-plugin-sitemap in /packages/website

Bumps [gatsby-plugin-sitemap](https://github.com/gatsbyjs/gatsby/tree/HEAD/packages/gatsby-plugin-sitemap) from 5.12.1 to 5.13.0.
- [Release notes](https://github.com/gatsbyjs/gatsby/releases)
- [Changelog](https://github.com/gatsbyjs/gatsby/blob/master/packages/gatsby-plugin-sitemap/CHANGELOG.md)
- [Commits](https://github.com/gatsbyjs/gatsby/commits/gatsby-plugin-sitemap@5.13.0/packages/gatsby-plugin-sitemap)

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

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

packages/website/package.json

@@ -21,7 +21,7 @@
     "gatsby-plugin-react-helmet": "5.12.1",
     "gatsby-plugin-robots-txt": "1.7.1",
     "gatsby-plugin-sharp": "4.13.0",
-    "gatsby-plugin-sitemap": "5.12.1",
+    "gatsby-plugin-sitemap": "5.13.0",
     "gatsby-plugin-svgr": "3.0.0-beta.0",
     "gatsby-source-filesystem": "4.12.1",
     "gatsby-transformer-sharp": "4.12.1",

packages/website/yarn.lock

@@ -6684,10 +6684,10 @@ gatsby-plugin-sharp@4.13.0:
     svgo "1.3.2"
     uuid "3.4.0"
 
-gatsby-plugin-sitemap@5.12.1:
-  version "5.12.1"
-  resolved "https://registry.yarnpkg.com/gatsby-plugin-sitemap/-/gatsby-plugin-sitemap-5.12.1.tgz#782a926a558d31663d4a8e66b9466c86df278568"
-  integrity sha512-Njdx91OF4xiFqHSSA3Yrnzxm4qu4xHyrhkiwQniFncoIGMI6IXqk9aDoxo3E1jZDWGPsI/2gzdcd8dBNQq9juA==
+gatsby-plugin-sitemap@5.13.0:
+  version "5.13.0"
+  resolved "https://registry.yarnpkg.com/gatsby-plugin-sitemap/-/gatsby-plugin-sitemap-5.13.0.tgz#7dd23d379b655bc49356a201eba90ddfce4b305e"
+  integrity sha512-KygCaEQYzSyik50vw6tU1fhUX/RtDv9nMFdgkcGKJT7BAsJvGRPDbxcwIkXTF6RmuNUCpnFC/bIqeXupPeNwZw==
   dependencies:
     "@babel/runtime" "^7.15.4"
     common-tags "^1.8.2"