Slack notification pipeline url one more fix

.github/workflows/get-xamarin-versions.yml

@@ -82,6 +82,6 @@ jobs:
         with:
           url: ${{ secrets.SLACK_CHANNEL_URL }}
           tool-name: 'Xamarin or Python'
-          pipeline-url: '${{ $env.GITHUB_SERVER_URL }}/${{ $env.GITHUB_REPOSITORY }}/actions/runs/${{ $env.GITHUB_RUN_ID }}'
+          pipeline-url: '${{ env.GITHUB_SERVER_URL }}/${{ env.GITHUB_REPOSITORY }}/actions/runs/${{ env.GITHUB_RUN_ID }}'
           image-url: 'https://avatars.githubusercontent.com/u/790012?s=200&v=4'
           text: "The build of the Xamarin or Python detection pipeline failed :progress-error:"