Need assistance with my first pipeline

Hi there,
I'm trying to set up my first pipeline using a maven container and not succeeding.

Error:
find or create container on worker 366bbec94d43: no image plugin configured

The env:
Ubuntu 20.04
Dockerized Concourse v7.7.1

docker-compose.yml

version: '3'

services:
db:
image: postgres
environment:
POSTGRES_DB: concourse
POSTGRES_USER: concourse_user
POSTGRES_PASSWORD: concourse_pass
logging:
driver: "json-file"
options:
max-file: "5"
max-size: "10m"

web:
image: concourse/concourse
command: web
links: [db]
depends_on: [db]
ports: ["8080:8080"]
volumes: ["./keys/web:/concourse-keys"]
environment:
CONCOURSE_EXTERNAL_URL: http://localhost:8080
CONCOURSE_POSTGRES_HOST: db
CONCOURSE_POSTGRES_USER: concourse_user
CONCOURSE_POSTGRES_PASSWORD: concourse_pass
CONCOURSE_POSTGRES_DATABASE: concourse
CONCOURSE_ADD_LOCAL_USER: test:test
CONCOURSE_MAIN_TEAM_LOCAL_USER: test
logging:
driver: "json-file"
options:
max-file: "5"
max-size: "10m"

worker:
image: concourse/concourse
command: worker
privileged: true
depends_on: [web]
volumes: ["./keys/worker:/concourse-keys"]
links: [web]
stop_signal: SIGUSR2
environment:
CONCOURSE_TSA_HOST: web:2222
# enable DNS proxy to support Docker's 127.x.x.x DNS server
CONCOURSE_GARDEN_DNS_PROXY_ENABLE: "true"
logging:
driver: "json-file"
options:
max-file: "5"
max-size: "10m"

Task yaml:

resources:

• name: git-repo
  type: git
  icon: github
  source:
  uri: https://github.com/myjavarepo/java.git
  branch: master

jobs:

• name: maven_install
  serial: true
  plan:

  • get: git-repo
    trigger: true

  • task: maven-package
    privileged: true
    config:
    platform: linux
    image_resource:
    type: registry-image #tried also docker-image
    source:
    repository: maven
    tag: 3.3.9-jdk-8

    inputs:
    - name: git-repo

    run:
    path: mvn
    args: ["-f", "git-repo/pom.xml", "clean install -DskipTests=true"]
    user: root

Any help will be highly appreciated.

Thanks!