Add conditional check for NuGet API key in publish step

Author: swedishkid

.github/workflows/ci-cd.yml

@@ -88,9 +88,12 @@ jobs:
       run: dotnet pack ${{ env.PROJECT_PATH }} --no-build --configuration Release -p:PackageVersion=${{ steps.gitversion.outputs.semVer }}
 
     - name: Publish to NuGet
+      if: ${{ secrets.NUGET_API_KEY != '' }}
+      env:
+        NUGET_API_KEY: ${{ secrets.NUGET_API_KEY }}
       run: |
         for package in TypescriptClientGenerator/bin/Release/*.nupkg; do
-          dotnet nuget push "$package" --api-key ${{ secrets.NUGET_API_KEY }} --source https://api.nuget.org/v3/index.json --skip-duplicate
+          dotnet nuget push "$package" --api-key "$NUGET_API_KEY" --source https://api.nuget.org/v3/index.json --skip-duplicate
         done
       
     - name: Upload release artifacts