refactor tests for readability (#51051)
You'll probably want to disable whitespace in the diff
## Description
This allows for better editor support by using `describe` or functions called `describe` with the same syntax instead of custom names.
Changes:
- `nextTestSetup` can be used instead of `createNextDescribe` keeping the same behaviour but being called inside a `describe` "block" (not applied everywhere)
- `getSnapshotTestDescribe` replaced with a custom `describe.each`
- `sandbox` helper function for `acceptance`/`acceptance-app` merged into a single shared one
- `outdent` to remove the indent from inline files in tests which helps with consistent snapshots
