chore(deps): bump flask from 1.1.2 to 2.0.0 in /tests/apps/multi
chore(deps): bump flask from 1.1.2 to 2.0.0 in /tests/apps/multi

Bumps [flask](https://github.com/pallets/flask) from 1.1.2 to 2.0.0.
- [Release notes](https://github.com/pallets/flask/releases)
- [Changelog](https://github.com/pallets/flask/blob/main/CHANGES.rst)
- [Commits](https://github.com/pallets/flask/compare/1.1.2...2.0.0)

Signed-off-by: dependabot[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@github.com>
dokku/dokku,dokku/dokku,claytonbrown/dokku,progrium/dokku,progrium/dokku,dokku/dokku,claytonbrown/dokku,dokku/dokku,progrium/dokku,claytonbrown/dokku,progrium/dokku,progrium/dokku,dokku/dokku,claytonbrown/dokku,dokku/dokku,dokku/dokku,claytonbrown/dokku,claytonbrown/dokku,progrium/dokku,progrium/dokku,progrium/dokku,dokku/dokku,claytonbrown/dokku,claytonbrown/dokku