chore: add fetch funtcion & add tests to helper module

packages/helper/package.json

@@ -0,0 +1,18 @@
+{
+  "name": "helper",
+  "version": "0.0.0",
+  "license": "MIT",
+  "main": "dist/index.js",
+  "types": "dist/index.d.ts",
+  "scripts": {
+    "lint": "TIMING=1 eslint \"**/*.ts*\"",
+    "build": "tsc",
+    "test": "FORCE_COLOR=1 yarn node --experimental-vm-modules $(yarn bin jest --passWithNoTests)"
+  },
+  "dependencies": {
+    "isomorphic-unfetch": "^4.0.2"
+  },
+  "devDependencies": {
+    "config": "*"
+  }
+}