Fix manifest generation step for e2e test (#6452)

generate-manifest.sh generates manifests to the standard output by default,
this means all feature changes in test.sh does not take effect now
without file redirection. Add it back to save the changes to the local antrea.yml.

Signed-off-by: Lan Luo <luola@vmware.com>

ci/jenkins/test.sh

@@ -530,10 +530,10 @@ function deliver_antrea {
     chmod -R g-w build/images/base
     if [[ "$BUILD_TAG" != "latest" ]]; then
         DOCKER_REGISTRY="${DOCKER_REGISTRY}" ./hack/build-antrea-linux-all.sh --build-tag ${BUILD_TAG} --pull
-        IMG_TAG="${BUILD_TAG}" ./hack/generate-manifest.sh $MANIFEST_ARGS
+        IMG_TAG="${BUILD_TAG}" ./hack/generate-manifest.sh $MANIFEST_ARGS > build/yamls/antrea.yml
     else
         DOCKER_REGISTRY="${DOCKER_REGISTRY}" ./hack/build-antrea-linux-all.sh --pull
-        ./hack/generate-manifest.sh $MANIFEST_ARGS
+        ./hack/generate-manifest.sh $MANIFEST_ARGS > build/yamls/antrea.yml
     fi
     make flow-aggregator-image