fix(UnitTests): Fixing "Cannot find module @cornerstonejs/core" error while running unit tests (#5148)

extensions/default/package.json

@@ -29,7 +29,9 @@
     "dev:dicom-pdf": "yarn run dev",
     "build": "cross-env NODE_ENV=production webpack --config .webpack/webpack.prod.js",
     "build:package-1": "yarn run build",
-    "start": "yarn run dev"
+    "start": "yarn run dev",
+    "test:unit": "jest --watchAll",
+    "test:unit:ci": "jest --ci --runInBand --collectCoverage --passWithNoTests"
   },
   "peerDependencies": {
     "@ohif/core": "3.11.0-beta.81",