Remove nerdctl workaround (#37)

node/Dockerfile

@@ -6,19 +6,6 @@ ARG TARGETARCH
 RUN apt-get update -yq && \
     apt-get install -yq --no-install-recommends wget apparmor apparmor-utils jq openssh-server sudo
 
-# Gardener's cloud-config-downloader still needs the docker CLI to be present in the image for preloading the hyperkube image,
-# see https://github.com/gardener/gardener/issues/4673
-# Install nerdctl as a (mostly) docker-compatible replacement and fool the cloud-config-downloader with a small wrapper
-# this is quite hacky but relieves us from installing docker here
-ARG NERDCTL_VERSION=1.6.0
-RUN curl -Lo /tmp/nerdctl.tar.gz https://github.com/containerd/nerdctl/releases/download/v$NERDCTL_VERSION/nerdctl-$NERDCTL_VERSION-$TARGETOS-$TARGETARCH.tar.gz && \
-    tar Cxzvvf /usr/local/bin /tmp/nerdctl.tar.gz && \
-    rm -f /tmp/nerdctl.tar.gz
-
-# add our small nerdctl wrapper and disguise it as docker
-COPY docker /usr/bin/docker
-RUN chmod +x /usr/bin/docker
-
 # remove kind's kubelet unit
 RUN rm -f /etc/systemd/system/kubelet.service && \
     rm -rf /etc/systemd/system/kubelet.service.d/