Ensure restore before building docfx

Author: dotMorten

.github/workflows/ghpages.yml

@@ -18,6 +18,13 @@ jobs:
     - name: Setup Visual Studio Command Prompt
       uses: microsoft/[email protected]
 
+    - name: Restore
+      run: |
+        msbuild /restore /t:Restore src/Toolkit/Toolkit.WPF/Esri.ArcGISRuntime.Toolkit.WPF.csproj /p:Configuration=Release
+        msbuild /restore /t:Restore src/Toolkit/Toolkit.WinUI/Esri.ArcGISRuntime.Toolkit.WinUI.csproj /p:Configuration=Release
+        msbuild /restore /t:Restore src/Toolkit/Toolkit.UWP/Esri.ArcGISRuntime.Toolkit.UWP.csproj /p:Configuration=Release
+        msbuild /restore /t:Restore src/Toolkit/Toolkit.Maui/Esri.ArcGISRuntime.Toolkit.Maui.csproj /p:Configuration=Release
+
     - name: Download DocFX
       run: |
         mkdir .tools/docfx