add SpaProxyKeepRunning

Author: surayya-MS

src/Middleware/Spa/SpaProxy/src/build/Microsoft.AspNetCore.SpaProxy.targets

@@ -12,7 +12,8 @@
       <_SpaProxyServerLaunchConfigLines Include="    &quot;ServerUrl&quot;: &quot;$(SpaProxyServerUrl)&quot;," />
       <_SpaProxyServerLaunchConfigLines Include="    &quot;LaunchCommand&quot;: &quot;$(SpaProxyLaunchCommand)&quot;," />
       <_SpaProxyServerLaunchConfigLines Include="    &quot;WorkingDirectory&quot;: &quot;$(_SpaRootFullPath)&quot;," />
-      <_SpaProxyServerLaunchConfigLines Include="    &quot;MaxTimeoutInSeconds&quot;: &quot;$(SpaProxyTimeoutInSeconds)&quot;" />
+      <_SpaProxyServerLaunchConfigLines Include="    &quot;MaxTimeoutInSeconds&quot;: &quot;$(SpaProxyTimeoutInSeconds)&quot;," />
+      <_SpaProxyServerLaunchConfigLines Include="    &quot;KeepRunning&quot;: &quot;$(SpaProxyKeepRunning)&quot;" />
       <_SpaProxyServerLaunchConfigLines Include="  }" />
       <_SpaProxyServerLaunchConfigLines Include="}" />
     </ItemGroup>