e2e: use docker v29.x dind as default

Also remove groupadd which looks to be redundant now.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

e2e/compose-env.yaml

@@ -4,7 +4,7 @@ services:
     image: 'registry:3'
 
   engine:
-      image: 'docker:${ENGINE_VERSION:-28}-dind'
+      image: 'docker:${ENGINE_VERSION:-29}-dind'
       privileged: true
       command: ['--insecure-registry=registry:5000', '--experimental']
       environment:

e2e/testdata/Dockerfile.connhelper-ssh

@@ -2,16 +2,13 @@
 
 # ENGINE_VERSION is the version of the (docker-in-docker) Docker Engine to
 # test against.
-ARG ENGINE_VERSION=28
+ARG ENGINE_VERSION=29
 
 FROM docker:${ENGINE_VERSION}-dind
 
 # the openssh-client update is needed for security reasons when using docker:23.0-dind, currently maintained as an lts by mirantis
 RUN apk --no-cache add openssl openssh-client openssh-server shadow && \
  apk --no-cache upgrade openssl openssh-client openssh-server &&  \
-  # TODO(krissetto): `groupadd` can be removed once we only test against moby >= v24
-  # see https://github.com/docker-library/docker/pull/470
-  groupadd -f docker && \
   useradd --create-home --shell /bin/sh --password $(head -c32 /dev/urandom | base64) penguin && \
   usermod -aG docker penguin && \
   ssh-keygen -A