Add TopCP CI container build

.github/workflows/topcp.yaml

@@ -0,0 +1,35 @@
+name: Builds ATLAS TopCPToolkit science image
+on:
+  push:
+
+env:
+  ANALYSISBASE_TAG: 25.2.45
+  TOPCPTOOLKIT_TAG: 2.17.0
+
+jobs:
+  docker:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/[email protected]
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v2
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v2
+      - name: Login to Docker Hub
+        uses: docker/login-action@v3
+        with:
+          username: ${{ secrets.DOCKER_USERNAME }}
+          password: ${{ secrets.DOCKER_PASSWORD }}
+      - name: Build and push
+        uses: docker/build-push-action@v3
+        with:
+          context: TopCP
+          push: ${{ github.ref == 'refs/heads/main' }}
+          build-args: |
+            ANALYSIS_BASE_VERSION=${{ env.ANALYSISBASE_TAG }}
+            TOPCPTOOLKIT_TAG=${{ env.TOPCPTOOLKIT_TAG }}
+          secrets: |
+            GIT_KEY=${{ secrets.GITLAB_TOKEN }}
+          tags: sslhep/servicex_science_image_topcp:${{ env.TOPCPTOOLKIT_TAG }}-${{ env.ANALYSISBASE_TAG }}
+          platforms: linux/amd64,linux/arm64