Bump code-push from 3.0.1 to 3.1.5 in /mobileapp

Bumps [code-push](https://github.com/Microsoft/code-push) from 3.0.1 to 3.1.5.
- [Release notes](https://github.com/Microsoft/code-push/releases)
- [Changelog](https://github.com/microsoft/code-push/blob/master/tsconfig-release.json)
- [Commits](microsoft/code-push@v3.0.1...v3.1.5)

---
updated-dependencies:
- dependency-name: code-push
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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