Update dependency gatsby to v4 [SECURITY]

Author: renovate[bot]

package.json

@@ -10,7 +10,7 @@
     "url": "https://toddbirchard.com"
   },
   "dependencies": {
-    "gatsby": "^2.24.47",
+    "gatsby": "^4.0.0",
     "gatsby-image": "^2.4.14",
     "gatsby-plugin-manifest": "^2.4.22",
     "gatsby-plugin-offline": "^3.2.22",