Update dependency gatsby-plugin-netlify to v5

Author: renovate[bot]

package.json

@@ -22,7 +22,7 @@
     "gatsby-plugin-google-analytics": "2.11.0",
 
     "gatsby-plugin-manifest": "2.12.1",
-    "gatsby-plugin-netlify": "2.11.1",
+    "gatsby-plugin-netlify": "5.0.0",
     "gatsby-plugin-offline": "3.10.2",
     "gatsby-plugin-webpack-bundle-analyser-v2": "1.1.20",