[CI] Fix pipeline template artifacts struct bug and cleanup bug

Signed-off-by: liushilongbuaa <shilongliu@microsoft.com>

.azure-pipelines/azure-pipelines-image-template.yml

@@ -45,7 +45,9 @@ jobs:
           ENABLE_DOCKER_BASE_PULL=y make PLATFORM=$(PLATFORM_AZP) PLATFORM_ARCH=$(PLATFORM_ARCH) configure
         displayName: 'Make configure'
     postSteps:
-      - publish: $(System.DefaultWorkingDirectory)/target
+      - script: cp target -r $(Build.ArtifactStagingDirectory)/
+        displayName: Copy Artifacts
+      - publish:  $(Build.ArtifactStagingDirectory)
         artifact: 'sonic-buildimage.$(GROUP_NAME)$(GROUP_EXTNAME)'
         displayName: "Archive sonic image"
       - ${{ parameters.postSteps }}

.azure-pipelines/cleanup.yml

@@ -10,8 +10,5 @@ steps:
     if sudo [ -f dockerfs/var/run/docker.pid ] ; then
         pid=`sudo cat dockerfs/var/run/docker.pid` ; sudo kill $pid
     fi
-    sudo rm -rf dockerfs
-    sudo rm -rf fsroot
-    username=$(id -un)
-    sudo chown -R ${username}.${username} .
+    sudo rm -rf $(ls -A1)
   displayName: "Clean Workspace"