Update DOCKER_DASH_COMPOSE_VERSION default to v2 (#920)

* Update DOCKER_DASH_COMPOSE_VERSION default to v2

Changed it because devcontainer-feature.json documentation indicates that it's the default version.

* Update devcontainer-feature.json version to 1.4.4

src/docker-outside-of-docker/devcontainer-feature.json

 {
     "id": "docker-outside-of-docker",
-    "version": "1.4.3",
+    "version": "1.4.4",
     "name": "Docker (docker-outside-of-docker)",
     "documentationURL": "https://github.com/devcontainers/features/tree/main/src/docker-outside-of-docker",
     "description": "Re-use the host docker socket, adding the Docker CLI to a container. Feature invokes a script to enable using a forwarded Docker socket within a container to run Docker commands.",

src/docker-outside-of-docker/install.sh

@@ -10,7 +10,7 @@
 DOCKER_VERSION="${VERSION:-"latest"}"
 USE_MOBY="${MOBY:-"true"}"
 MOBY_BUILDX_VERSION="${MOBYBUILDXVERSION:-"latest"}"
-DOCKER_DASH_COMPOSE_VERSION="${DOCKERDASHCOMPOSEVERSION:-"v1"}" # v1 or v2 or none
+DOCKER_DASH_COMPOSE_VERSION="${DOCKERDASHCOMPOSEVERSION:-"v2"}" # v1 or v2 or none
 
 ENABLE_NONROOT_DOCKER="${ENABLE_NONROOT_DOCKER:-"true"}"
 SOURCE_SOCKET="${SOURCE_SOCKET:-"/var/run/docker-host.sock"}"