fix #161; use default minify, not esbuild

Author: mbostock

bin/build.ts

@@ -62,8 +62,8 @@ export default async function run(args?: string[]): Promise<void> {
     root: values.root,
     base: values.base,
     build: {
-      minify: values.minify ? "esbuild" : false,
-      cssMinify: values.minify ? "esbuild" : false,
+      minify: values.minify,
+      cssMinify: values.minify,
       outDir: values.out,
       emptyOutDir: values.empty,
       rollupOptions: {