fix: add Docker Hub login before building image

[camory]

Motivation

The Docker image build is failing with authentication error:

401 Unauthorized
{"details":"access token has insufficient scopes"}

This prevents the Docker image from being published to Docker Hub.

Description

Root Cause

The Jib Maven plugin needs Docker Hub credentials to push images. It was trying to use credentials from the Docker config file (~/.docker/config.json), but this file didn't exist or didn't have valid credentials.

The error message indicates that Jib couldn't authenticate:

Build image failed, perhaps you should make sure your credentials for 
'registry-1.docker.io/dockerhubaneo/armonik-dynamic-java-worker' are set up correctly

Solution

Add an explicit Docker login step before building the image:

      - name: Log in to Docker Hub
        uses: docker/login-action@v3
        with:
          username: ${{ secrets.DOCKER_HUB_LOGIN }}
          password: ${{ secrets.DOCKER_HUB_TOKEN }}

This creates credentials in ~/.docker/config.json that Jib automatically reads when pushing images.