Update nextjs monorepo to ^12.3.4

Author: renovate[bot]

package-lock.json

@@ -19,7 +19,7 @@
     "gray-matter": "^4.0.3",
     "js-yaml": "^4.1.0",
     "mdi-react": "^8.2.0",
-    "next": "^12.0.7",
+    "next": "^12.3.4",
     "next-mdx-remote": "^3.0.8",
     "prismjs": "^1.25.0",
     "prism-react-renderer": "^1.2.1",
@@ -33,8 +33,8 @@
     "styled-components": "^5.3.3"
   },
   "devDependencies": {
-    "@next/bundle-analyzer": "^12.0.7",
-    "@next/eslint-plugin-next": "^12.0.7",
+    "@next/bundle-analyzer": "^12.3.4",
+    "@next/eslint-plugin-next": "^12.3.4",
     "@sourcegraph/eslint-config": "^0.32.0",
     "@sourcegraph/prettierrc": "^3.0.3",
     "@types/js-yaml": "4.0.5",