chore(deps): update dependency gatsby-plugin-graphql-codegen to v3

Author: renovate[bot]

package.json

@@ -38,7 +38,7 @@
     "@types/reach__router": "1.3.6",
     "@types/react-helmet": "6.1.0",
     "@types/reactstrap": "8.5.2",
-    "gatsby-plugin-graphql-codegen": "2.7.1",
+    "gatsby-plugin-graphql-codegen": "3.1.1",
     "prettier": "2.1.2",
     "ts-node": "9.0.0"
   },