build: set minimal node version in build script to v20

Author: wolfy1339

scripts/build.mjs

@@ -30,7 +30,7 @@ async function main() {
       outdir: "pkg/dist-node",
       bundle: true,
       platform: "node",
-      target: "node18",
+      target: "node20",
       format: "esm",
       ...sharedOptions,
     }),