Bump gatsby-plugin-offline from 2.2.10 to 4.3.0

Bumps [gatsby-plugin-offline](https://github.com/gatsbyjs/gatsby/tree/HEAD/packages/gatsby-plugin-offline) from 2.2.10 to 4.3.0.
- [Release notes](https://github.com/gatsbyjs/gatsby/releases)
- [Changelog](https://github.com/gatsbyjs/gatsby/blob/master/packages/gatsby-plugin-offline/CHANGELOG.md)
- [Commits](https://github.com/gatsbyjs/gatsby/commits/gatsby-plugin-offline@4.3.0/packages/gatsby-plugin-offline)

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

package.json

@@ -16,7 +16,7 @@
         "gatsby-plugin-feed": "^2.13.1",
         "gatsby-plugin-google-analytics": "^2.11.0",
         "gatsby-plugin-manifest": "^2.12.1",
-        "gatsby-plugin-offline": "^2.0.25",
+        "gatsby-plugin-offline": "^3.10.2",
         "gatsby-plugin-react-helmet": "^3.10.0",
         "gatsby-plugin-sharp": "^2.0.32",
         "gatsby-plugin-styled-components": "^3.10.0",