Nightly job to push service feedback to the performance platform

Don't merge until the following are done:

- [x] merge https://github.com/alphagov/gds-api-adapters/pull/115 and bump `gds-api-adapters` version
- [x] update the `gds-api-adapters` in Gemfile
- [x] fix the data issue with transaction slugs being in the form of `done/<slug>` rather than `<slug>` (https://github.com/alphagov/feedback/pull/108, https://github.com/alphagov/support/pull/128)