Some components are not compatible with styled-components v6

Some components that use `react-select` can break (or fail in test environmets) when using `styled-components` latest (tested with 6.0.5).

- `@freenow/wave` version: 1.32.0 (and probably may minors before)

### What was expected to happen?

Eg.: `PhoneInput`, when user opens the Country select, makes the example app (below) crash with:

```
Cannot read properties of undefined (reading 'borderRadius')
```

### Reproduction

https://codesandbox.io/s/styled-components-6-issue-gffvqg

Start with the PhoneInput component and reproduce the failure using the linked CodeSandbox with styled-components 6.0.5. Trace the react-select integration that reads borderRadius, then verify that opening the Country select no longer crashes in the example or test environment.

Written by the indexing model from the issue text.