chore(medusa-dev-cli): Cleanup plugin setup (#4421)

FIXES CORE-1420

does not include ts migration

packages/medusa-dev-cli/jest.config.js

@@ -0,0 +1,13 @@
+module.exports = {
+  globals: {
+    "ts-jest": {
+      tsConfig: "tsconfig.spec.json",
+      isolatedModules: false,
+    },
+  },
+  transform: {
+    "^.+\\.[jt]s?$": "ts-jest",
+  },
+  testEnvironment: `node`,
+  moduleFileExtensions: [`js`, `jsx`, `ts`, `tsx`, `json`],
+}