fix(ci): Add logic to check and calculate secundary image to use (#1529)

Add logic to check if the `BUILD_RELEASE_VERSION` tag is available in
docker registry, if not calculate the previous version to use as
secondary image. This fix the issue in test using the `secondary image`
and bumping the `NODE_VERSION`. (e.g #1495)

.gitlab/pipeline/zombienet/polkadot.yml

@@ -7,10 +7,18 @@
     - export BUILD_RELEASE_VERSION="$(cat ./artifacts/BUILD_RELEASE_VERSION)" # from build-linux-stable job
     - export DEBUG=zombie,zombie::network-node
     - export ZOMBIENET_INTEGRATION_TEST_IMAGE="${POLKADOT_IMAGE}":${PIPELINE_IMAGE_TAG}
-    - export ZOMBIENET_INTEGRATION_TEST_SECONDARY_IMAGE="docker.io/parity/polkadot:${BUILD_RELEASE_VERSION}"
     - export COL_IMAGE="${COLANDER_IMAGE}":${PIPELINE_IMAGE_TAG}
     - export CUMULUS_IMAGE="docker.io/paritypr/polkadot-parachain-debug:${DOCKER_IMAGES_VERSION}"
     - export MALUS_IMAGE="${MALUS_IMAGE}":${PIPELINE_IMAGE_TAG}
+    - IMAGE_AVAILABLE=$(curl -o /dev/null -w "%{http_code}" -I -L -s https://registry.hub.docker.com/v2/repositories/parity/polkadot/tags/${BUILD_RELEASE_VERSION})
+    - if [ $IMAGE_AVAILABLE -eq 200 ]; then
+        export ZOMBIENET_INTEGRATION_TEST_SECONDARY_IMAGE="docker.io/parity/polkadot:${BUILD_RELEASE_VERSION}";
+      else
+        echo "Getting the image to use as SECONDARY, using ${BUILD_RELEASE_VERSION} as base";
+        VERSIONS=$(curl -L -s 'https://registry.hub.docker.com/v2/repositories/parity/polkadot/tags/' | jq -r '.results[].name'| grep -E "v[0-9]" |grep -vE "[0-9]-");
+        VERSION_TO_USE=$(echo "${BUILD_RELEASE_VERSION}\n$VERSIONS"|sort -r|grep -A1 "${BUILD_RELEASE_VERSION}"|tail -1);
+        export ZOMBIENET_INTEGRATION_TEST_SECONDARY_IMAGE="docker.io/parity/polkadot:${VERSION_TO_USE}";
+      fi
     - echo "Zombienet Tests Config"
     - echo "gh-dir ${GH_DIR}"
     - echo "local-dir ${LOCAL_DIR}"