Bump semver from 7.3.2 to 7.3.4 in /app

Bumps [semver](https://github.com/npm/node-semver) from 7.3.2 to 7.3.4.
- [Release notes](https://github.com/npm/node-semver/releases)
- [Changelog](https://github.com/npm/node-semver/blob/master/CHANGELOG.md)
- [Commits](https://github.com/npm/node-semver/compare/v7.3.2...v7.3.4)

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