FIX broken github action due to outdated buildx

Buildx failed the pipeline and there's some deprecation warnings in
there, so decided to update every stage of the build process to the
current latest see if it fixes it.

The checkout action isn't necessary anymore because we're in the git
context by default.

.github/workflows/main.yml

@@ -22,10 +22,11 @@ jobs:
     # Steps represent a sequence of tasks that will be executed as part of the job
     steps:
       # Checks-out your repository under $GITHUB_WORKSPACE, so your job can access it
-      - uses: actions/checkout@v2
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v3
 
       - name: Login to Docker Hub
-        uses: docker/login-action@v1
+        uses: docker/login-action@v3
         with:
           username: ${{ secrets.DOCKER_HUB_USERNAME }}
           password: ${{ secrets.DOCKER_HUB_ACCESS_TOKEN }}
@@ -47,15 +48,12 @@ jobs:
            type=sha
 
       - name: Set up Docker Buildx
-        id: buildx
-        uses: docker/setup-buildx-action@v1
+        uses: docker/setup-buildx-action@v3
 
       - name: Build and push
         id: docker_build
-        uses: docker/build-push-action@v2
+        uses: docker/build-push-action@v5
         with:
-          context: ./
-          file: ./Dockerfile
           push: ${{ github.event_name != 'pull_request'  }}
           tags: ${{ steps.meta.outputs.tags  }}
           labels: ${{ steps.meta.outputs.labels  }}