Update publish-nuget.yml

Author: pergerch

.github/workflows/publish-nuget.yml

@@ -12,6 +12,12 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v2
+    - uses: actions/setup-dotnet@v1.9.0
+      with:
+        dotnet-version: | 
+          3.1.x
+          5.0.x
+          6.0.x
     - name: Publish NuGet
       id: publishNuGet
       uses: brandedoutcast/publish-nuget@v2.5.5
@@ -35,4 +41,4 @@ jobs:
       if: ${{steps.publishNuGet.outputs.SYMBOLS_PACKAGE_NAME != ''}}
       with:
         name: ${{steps.publishNuGet.outputs.SYMBOLS_PACKAGE_NAME}}
-        path: ${{steps.publishNuGet.outputs.SYMBOLS_PACKAGE_PATH}}
+        path: ${{steps.publishNuGet.outputs.SYMBOLS_PACKAGE_PATH}}