ci: Conditionning docker step with the presence of docker credentials

Signed-off-by: Vincent Boutour <bob@vibioh.fr>

.github/workflows/build.yaml

@@ -38,11 +38,6 @@ jobs:
     steps:
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v1
-      - name: Login to DockerHub
-        uses: docker/login-action@v1
-        with:
-          username: ${{ secrets.DOCKER_USER }}
-          password: ${{ secrets.DOCKER_PASS }}
       - uses: actions/checkout@v2
       - uses: actions/setup-go@v2
         with:
@@ -51,6 +46,22 @@ jobs:
         run: |
           curl --disable --silent --show-error --location --max-time 30 "https://raw.githubusercontent.com/ViBiOh/scripts/main/bootstrap" | bash -s "release"
           ./scripts/release build
+          DOCKER_IMAGE="${{ secrets.DOCKER_USER }}/$(make name)" IMAGE_VERSION="$(make version)" ./scripts/release build
+      - name: Login to DockerHub
+        if: env.DOCKER_USER && env.DOCKER_PASS
+        env:
+          DOCKER_USER: ${{ secrets.DOCKER_USER }}
+          DOCKER_PASS: ${{ secrets.DOCKER_PASS }}
+        uses: docker/login-action@v1
+        with:
+          username: ${{ secrets.DOCKER_USER }}
+          password: ${{ secrets.DOCKER_PASS }}
+      - name: Docker
+        if: env.DOCKER_USER && env.DOCKER_PASS
+        env:
+          DOCKER_USER: ${{ secrets.DOCKER_USER }}
+          DOCKER_PASS: ${{ secrets.DOCKER_PASS }}
+        run: |
           DOCKER_IMAGE="${{ secrets.DOCKER_USER }}/$(make name)" IMAGE_VERSION="$(make version)" ./scripts/release docker
 
   publish: