Pocketbase

- Shallow copy the realtime subscribe `options` argument for consistency with the other methods ([308](https://github.com/pocketbase/js-sdk/issues/308)).

- Fixed the `requestKey` handling in `authWithOAuth2({...})` to allow manually cancelling the entire OAuth2 pending request flow using `pb.cancelRequest(requestKey)`.
_Due to the [`window.close` caveats](https://developer.mozilla.org/en-US/docs/Web/API/Window/close) note that the OAuth2 popup window may still remain open depending on which stage of the OAuth2 flow the cancellation has been invoked._

- Enforce temporary the `atob` polyfill for ReactNative until [Expo 51+ and React Native v0.74+ `atob` fix get released](https://github.com/reactwg/react-native-releases/issues/287).

- Exported `HealthService` types ([289](https://github.com/pocketbase/js-sdk/issues/289)).

- Manually update the verified state of the current matching `AuthStore` model on successful "confirm-verification" call.

- Manually clear the current matching `AuthStore` on "confirm-email-change" call because previous tokens are always invalidated.

- Updated the `fetch` mock tests to check also the sent body params.

- Formatted the source and tests with prettier.

**⚠️ This release works only with PocketBase v0.21.0+ due to changes of how the `multipart/form-data` body is handled.**

- Properly sent json body with `multipart/form-data` requests.
_This should fix the edge cases mentioned in the v0.20.3 release._

- Gracefully handle OAuth2 redirect error with the `authWithOAuth2()` call.