Bump node-fetch, prop-types and react-native in /examples

Bumps [node-fetch](https://github.com/node-fetch/node-fetch) to 2.6.7 and updates ancestor dependencies [node-fetch](https://github.com/node-fetch/node-fetch), [prop-types](https://github.com/facebook/prop-types) and [react-native](https://github.com/facebook/react-native). These dependencies need to be updated together.


Updates `node-fetch` from 1.7.3 to 2.6.7
- [Release notes](https://github.com/node-fetch/node-fetch/releases)
- [Commits](node-fetch/node-fetch@1.7.3...v2.6.7)

Updates `prop-types` from 15.6.1 to 15.8.1
- [Release notes](https://github.com/facebook/prop-types/releases)
- [Changelog](https://github.com/facebook/prop-types/blob/main/CHANGELOG.md)
- [Commits](facebook/prop-types@v15.6.1...v15.8.1)

Updates `react-native` from 0.60.0 to 0.70.6
- [Release notes](https://github.com/facebook/react-native/releases)
- [Changelog](https://github.com/facebook/react-native/blob/main/CHANGELOG.md)
- [Commits](facebook/react-native@v0.60.0...v0.70.6)

---
updated-dependencies:
- dependency-name: node-fetch
  dependency-type: indirect
- dependency-name: prop-types
  dependency-type: direct:production
- dependency-name: react-native
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>