Bump node-fetch from 2.6.0 to 2.6.7 in /TestingApp

Bumps [node-fetch](https://github.com/node-fetch/node-fetch) from 2.6.0 to 2.6.7.
- [Release notes](https://github.com/node-fetch/node-fetch/releases)
- [Commits](node-fetch/node-fetch@v2.6.0...v2.6.7)

---
updated-dependencies:
- dependency-name: node-fetch
  dependency-type: direct:development
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

TestingApp/package-lock.json

@@ -28,7 +28,7 @@
     "isomorphic-fetch": "^3.0.0",
     "jest": "^26.6.3",
     "metro-react-native-babel-preset": "^0.66.2",
-    "node-fetch": "2.6.0",
+    "node-fetch": "2.6.7",
     "react-test-renderer": "17.0.2",
     "ts-jest": "25.3.0"
   },