Fix how to push to nuget

Author: pmiossec

.github/workflows/dotnetcore.yml

@@ -23,7 +23,7 @@ jobs:
       uses: NuGet/[email protected]
 
     - name: Add private GitHub registry to NuGet
-      run: nuget sources add -name "nuget" -Source https://api.nuget.org/v3/index.json -Username pmiossec -Password ${{ secrets.NUGET_PUSH_TOKEN }}
+      run: nuget setApiKey ${{ secrets.NUGET_PUSH_TOKEN }}
 
     - name: Push to GitHub nuget feed
-      run: nuget push "src/GitExtensions.AzureDevOpsCommitMessage/bin/Release/GitExtensions.AzureDevOpsCommitMessage.*.nupkg" -Source "nuget"
+      run: nuget push "src/GitExtensions.AzureDevOpsCommitMessage/bin/Release/GitExtensions.AzureDevOpsCommitMessage.*.nupkg" -Source https://api.nuget.org/v3/index.json