fix other directory variable

Author: gapra-msft

azurePipelineTemplates/build_linux.yml

@@ -32,10 +32,10 @@ steps:
     displayName: 'Build SE Integration'
   - script: |
       linux_dir="$(System.DefaultWorkingDirectory)/azcopy_linux_${{ parameters.host_architecture }}_$(azcopy_version)"
-      echo "##vso[task.setvariable variable=linux_dir]linux_dir"
+      echo "##vso[task.setvariable variable=linux_dir]$linux_dir"
       
       linux_se_dir="$(System.DefaultWorkingDirectory)/azcopy_linux_se_${{ parameters.host_architecture }}_$(azcopy_version)"
-      echo "##vso[task.setvariable variable=linux_se_dir]linux_se_dir"
+      echo "##vso[task.setvariable variable=linux_se_dir]$linux_se_dir"
       
       mkdir -p $linux_dir
       mkdir -p $linux_se_dir