Empty commit transporting the release notes after repository split

``` noteworthy developer github.com/gardener/terraformer #33 @DockToFuture
The Google provider plugins have been upgraded to `v3.4.0`.
```

``` improvement operator
Added support for custom root disk size (originally contributed by @afritzler via [gardener-attic/gardener-extensions#567](https://github.com/gardener/gardener-extensions#567)).
```

``` improvement operator
added integration tests for health checks for all extensions (originally contributed by @danielfoehrKn via [gardener-attic/gardener-extensions#563](https://github.com/gardener/gardener-extensions#563)).
```