added min version for esm bundle

bundle.js

@@ -51,6 +51,21 @@ const runBuild = async () => {
     console.log(e);
     process.exit(1);
   });
+
+  build({
+    entryPoints: ['./src/index.ts'],
+    minify: true,
+    bundle: true,
+    outfile: './bundles/esm.bundle.min.js',
+    platform: 'browser',
+    target: ['es2020', 'chrome58', 'firefox57', 'safari11'],
+    format: 'esm',
+    globalName: 'rsdk'
+  }).catch((e) => {
+    console.log(e);
+    process.exit(1);
+  });
+
 };
 runBuild();