Ensure DevServer has the AspNetCore.App runtime in runtimeconfig.json (#23814)

Author: pranavkm

src/Components/WebAssembly/DevServer/src/Microsoft.AspNetCore.Components.WebAssembly.DevServer.csproj

@@ -38,4 +38,19 @@
     <NuspecProperty Include="PackageThirdPartyNoticesFile=$(PackageThirdPartyNoticesFile)" />
   </ItemGroup>
 
+  <Target Name="_FixupRuntimeConfig" BeforeTargets="_GenerateRuntimeConfigurationFilesInputCache">
+    <ItemGroup>
+      <_RuntimeFramework Include="@(RuntimeFramework)" />
+      <RuntimeFramework Remove="@(RuntimeFramework)" />
+      <RuntimeFramework Include="Microsoft.AspNetCore.App" FrameworkName="Microsoft.AspNetCore.App" Version="5.0.0-preview" />
+    </ItemGroup>
+  </Target>
+
+   <Target Name="_UndoRuntimeConfigWorkarounds" AfterTargets="GenerateBuildRuntimeConfigurationFiles">
+    <ItemGroup>
+      <RuntimeFramework Remove="@(RuntimeFramework)" />
+      <RuntimeFramework Include="@(_RuntimeFramework)" />
+    </ItemGroup>
+  </Target>
+
 </Project>