Added new script test:unit for only testing unit tests on npm run test:unit (#77)

Author: flora-jin

package.json

@@ -22,6 +22,8 @@
     "postinstall": "cd templates/Lambda4AppSyncHTTP && npm install && cd ../Lambda4AppSyncSDK && npm install && cd ../Lambda4AppSyncGraphSDK && npm install",
     "lint": "eslint neptune-for-graphql.mjs ./src",
     "test": "node --experimental-vm-modules node_modules/jest/bin/jest.js --coverage --runInBand --detectOpenHandles --config .jest.js",
+    "test:unit": "node --experimental-vm-modules node_modules/jest/bin/jest.js --coverage --runInBand --detectOpenHandles --config .jest.js --testPathPattern=src/test",
+    "test:integration": "node --experimental-vm-modules node_modules/jest/bin/jest.js --coverage --runInBand --detectOpenHandles --config .jest.js --testPathPattern=test/TestCases",
     "test:sdk": "node --experimental-vm-modules node_modules/jest/bin/jest.js --coverage --runInBand --detectOpenHandles --config .jest.js --testPathPattern=test/TestCases/Case07",
     "test:resolver": "node --experimental-vm-modules node_modules/jest/bin/jest.js --coverage --runInBand --detectOpenHandles --config .jest.js --testPathPattern=test/TestCases/Case01"
   },