[FLINK-37740][flink-docker] Fix GitHub snapshots workflow failure

Author: morazow

.github/workflows/snapshot.yml

@@ -36,49 +36,50 @@ jobs:
     strategy:
       max-parallel: 1
       matrix:
-        build:
+        java_version: [8, 11, 17, 21]
+        flink_version: [ 2.0-SNAPSHOT, 1.20-SNAPSHOT, 1.19-SNAPSHOT, 1.18-SNAPSHOT ]
+        include:
           - flink_version: 2.0-SNAPSHOT
-            java_version: [8, 11, 17, 21]
             branch: dev-master
           - flink_version: 1.20-SNAPSHOT
-            java_version: [ 8, 11, 17, 21 ]
             branch: dev-1.20
           - flink_version: 1.19-SNAPSHOT
-            java_version: [8, 11, 17, 21]
             branch: dev-1.19
           - flink_version: 1.18-SNAPSHOT
-            java_version: [8, 11, 17]
             branch: dev-1.18
+        exclude:
+          - flink_version: 1.18-SNAPSHOT
+            java_version: 21
     steps:
       - uses: actions/checkout@v4
         with:
-          ref: ${{ matrix.build.branch }}
+          ref: ${{ matrix.branch }}
 
-      - name: Set up QEMU
+      - name: "Set up QEMU"
         uses: docker/setup-qemu-action@v3
 
-      - name: Set up Docker Buildx
+      - name: "Set up Docker Buildx"
         uses: docker/setup-buildx-action@v3
 
-      - name: Log in to the Container registry
+      - name: "Log in to the Container registry"
         uses: docker/login-action@v3
         with:
           registry: ${{ env.REGISTRY }}
           username: ${{ github.actor }}
           password: ${{ secrets.GITHUB_TOKEN }}
 
-      - name: Prepare Dockerfiles and set env
+      - name: "Prepare Dockerfiles and set env"
         run: |
-          IMAGE_NAME=${{ matrix.build.flink_version }}-scala_2.12-java${{ matrix.build.java_version }}
+          IMAGE_NAME=${{ matrix.flink_version }}-scala_2.12-java${{ matrix.java_version }}
           echo "IMAGE_NAME=${IMAGE_NAME}" >> $GITHUB_ENV
           echo "TAG=${REGISTRY}/${OWNER}/${IMAGE_REPO}:${IMAGE_NAME}-debian" >> $GITHUB_ENV
-          ./add-custom.sh -u "https://s3.amazonaws.com/flink-nightly/flink-${{ matrix.build.flink_version }}-bin-scala_2.12.tgz" -j ${{ matrix.build.java_version }} -n ${IMAGE_NAME}
-          echo "DOCKER_FILE=$(ls ./*/*${{ matrix.build.flink_version }}*${{ matrix.build.java_version }}*/Dockerfile)" >> $GITHUB_ENV
+          ./add-custom.sh -u "https://s3.amazonaws.com/flink-nightly/flink-${{ matrix.flink_version }}-bin-scala_2.12.tgz" -j ${{ matrix.java_version }} -n ${IMAGE_NAME}
+          echo "DOCKER_FILE=$(ls ./*/*${{ matrix.flink_version }}*${{ matrix.java_version }}*/Dockerfile)" >> $GITHUB_ENV
 
-      - name: Environment
+      - name: "List environment variables"
         run: env
 
-      - name: Build and push Docker images (supported platforms)
+      - name: "Build and push Docker images (supported platforms)"
         uses: docker/bake-action@v4
         with:
           files: |