Merge pull request #314 from embroider-build/upgrade-node18

Require node 18+

Author: NullVoxPopuli

package.json

@@ -34,11 +34,10 @@
     "typescript": "^4.7.4"
   },
   "engines": {
-    "node": "16.* || >= 18"
+    "node": "18.* || >= 20"
   },
   "volta": {
-    "node": "16.20.1",
-    "yarn": "1.22.18",
+    "node": "18.20.5",
     "pnpm": "8.7.6"
   },
   "publishConfig": {